Not sure if you fall into the short attention span tl;dr crowd, but if you do...
Executive summary: POR has more than enough to offer the Knicks for Carmelo, if he waives his NTC. HOU has nothing the Kicks would want - NOTHING.
The only way NYK gets either Nurkic or Collins is if they also include Porzingis. And even then, I think POR would hesitate to give up Nurkic. He is such a great fit, on both ends of the court, with the rest of our roster. After the Nurk trade, our team 3FG% skyrocketed and we became a top 10 defense. That's how important he is to this team. Mason Plumlee isn't a bad player - great motor and one of the best passing bigs in the league, but he has limitations that Nurk doesn't have. On paper, the difference doesn't look that big. On the court, it's huge.
Even without Nukic and Collins, we have everything a rebuilding team, like the Knicks, could want.
We have a young, improving 23-year old proven NBA starter they covet in Maurice Harkless, who is locked in for three more years on a very team friendly, below market contract. HOU has nothing close to that.
We have a decent expiring contract in Ed Davis. He could be part of a package to make the salaries match and will be long gone and off their cap by the time they need to give extensions to Porzingis, Hernangomez and the rest of their young players. HOU's only significant expiring contract is Trevor Ariza. His salary is comparable to Davis', but supposedly CP3 doesn't want HOU to trade Ariza. This is the only trade asset where HOU is equal to POR, and you'd still need to include Ryan Anderson, or possibly Eric Gordon plus a few of the small non-guaranteed contracts Morey has been hording. Would either team for an Ariza + Gordon for Melo swap? It further depletes the Rockets already thin roster and it gives NYK two players over the age of 29 - one who is locked in for 3 more years. Not exactly something of interest to a rebuilding team.
POR also owns all of their future first round picks. HOU already gave up their 2018 first round pick in the CP3 trade. Due to the Ted Stepien Rule, that means 2020 is the first available first round pick the Rockets can trade. Do the Knicks really want to wait three years for what would likely be a pick in the late 20s? The Blazer can offer their 2018 first round pick and if necessary both their 2018 and 2020 picks.
POR also has a $12.9 million traded player exception from the Allen Crabbe trade. It cannot be used in combination with other salaries, but it happens to be a perfect match for Courtney Lee's salary. So, as part of a separate trade, we can also take one of the Knicks biggest contracts off their hands. At 32, Lee clearly doesn't fit in the the Knicks rebuilding plans. POR actually needs help at back up shooting guard after trading Crabbe. Lee would replace Crabbe's lost shooting, and is a much better defender than Crabbe. He would actually be a useful 3 and D guy coming of the bench for POR. Using that TPE for Lee would push POR back over the luxury tax threshold, but if Paul Allen wants Carmelo Anthony badly enough, he will bite the bullet and pay the tax. HOU has nothing comparable to offer NYK.
Portland also has other young players that are still on their rookie contracts than that Knicks may want. Noah Vonleh is still only 21 (will turn 22 later this month). So, age wise, he fits in well with their rebuilding plan. He has started over half of POR's games at PF the last two seasons. His offensive game is still immature, but he is an above average rebounder and excellent defender. He played much better next to Nurkic, than he did next to Plumlee. Over the last month of the season he scored in double digits 8 times and had 6 games with at least 11 rebounds. He would be great coming off the bench in New York. Portland drafted two guys in Collins and Swanigan that play the same position. So, Vonleh is expendable.
Finally, the other thing that has changed over the last month is almost every team that had enough cap space to act as a third party and absorb Ryan Anderson's contract has used that cap space up. BRK was Morey's best bet and Neil Olshey eliminated that option with the Allen Crabbe trade. Olshey killed two birds with one stone. He caused BRK to use up their cap space and acquired a $12.9 million TPE that could prove to be a valuable trade asset in the pursuit of Carmelo Anthony.
There is absolutely zero doubt that should Carmelo expands he list of acceptable destinations to include Portland, the Blazers easily have the assets to make it happen. They can offer the Knicks a package that includes a prove young player they covet on a team friendly contract (Harkless), an expiring contract to make the salaries work (Davis), an additional young player (Vonleh), one or more future first round draft picks (2018 or 2018 and 2020) and they have a huge TPE that can be used for the Knicks to offload a highly paid 32-year old who no longer fits their plans.
HOU can't come close to that. Right now, what HOU has to offer has negative net value to a rebuilding team. Ryan Anderson is a 1-dimensional 3-point shooter who has an absolutely terrible contract. He is also 29-years old, injury prone and doesn't play defense. He also plays the same position as the 22-year old face of the franchise that is the very heart of the Knicks rebuilding effort. Morey overpaid Anderson and nobody else wants to bail him out and take Ryan Anderson off his hands to help the Rockets get better. No rebuilding team wants Anderson, and even if they did, would not give up assets the Knicks would want. No contending team has the cap space to absorb Anderson's contract and wouldn't willingly help the competition get better if they could. Anderson is pretty much locked in as HOU's $20 million a year 4th option.
Face it, after the CP3 trade, the cupboard in HOU is bare. Acquiring one disgruntled star guts your roster. Acquiring two is damn near impossible. Morey shot his wad on the CP3 trade. He has nothing left to offer the Knicks and is desperately seeking another team to help him out. The problem is, HOU is so devoid of trade assets, he doesn't have anything anyone else would want either.
BNM
