A pick swap is how the Celtics got Jason Tatum. A swap doesn't always provide value, but when it does the value can be massive!
Yes I'd say most likely the value will be 0 or very little - but it has a very real potential for much more. Especially in 2029, Dame/Butler will be 40 and Riley over 80. That team is emptying assets to win now and very possibly will fail to properly reload later. That is a great time for us to take a roll of the dice on house money, and can be held until that 2029 time or flipped for an upgrade earlier if the Blazers get closer to winning now.
What is the chance the Heat are in the lottery in 2029? Let's say 50/50 even with their aging core that I'd argue is more likely to be in the lottery than not by then. Let's say odds the Blazers are in the playoffs then is also around 50/50, some would argue higher as our youth now should be in their prime then. So that gives us a 25% chance the Blazers upgrade their late pick to a lottery pick, 12.5% chance Blazers swap to better lottery pick, 12.5% chance Blazers swap to better late pick, and 50% chance there is no swap.
One way to grade this is think of the value of the 2030 unprotected pick today. I'd put about 80% of the value of that pick being the chance its in the lottery especially at the top of the lottery. Lottery picks are worth SOOOO much more than a mid to late 1st round pick. The Blazers retain nearly all of those 80% lottery benefits the same in the swap as if they held the pick outright!
So yes the 2028 and 2030 picks are clearly worth more - but that 2029 swap still has the majority of the value of those picks.