Other than rumblings that Detroit MAY have been interested, there was no indication that any team was interested in him at that level. Portland bid against itself as it did for Ant and Nurk the year before.
Portland gave up a future first rounder for Grant when he was two years younger and significantly cheaper... what's he going to be worth when he's 32 or 33 and getting paid so much under a CBA that is absolutely brutal with moving big contracts? It's not going to be much, if anything, positive and in the meantime we've got a veteran shooter who doesn't rebound but MAY help us win a few games that we shouldn't be trying to win as we rebuild.
And, yes, that is WAY TOO MUCH for a fourth option, or a third option that's the level of Grant, under the new CBA. The salary cap will go up, but the overall aim of the new CBA is to spread salaries out to more folks, rather than a few massive contracts, and we saw that yesterday in every signing (either in length or average per year or both) other than Grant's deal.