-Obama’s deal was indefensibly ass. There’s literally nothing positive that can be said for it because it was dumb.

The deal was sound, and there's lots of positive things to be said about it. Iran agreed to restrict their uranium enrichment. They agreed to monitoring and inspection. The result of those agreements was that Iran did not have any uranium enriched to weapons grade at any time that the deal was in effect. IOW, the agreement effectively neutralized the nuclear threat of Iran as much as any agreement can.

The main criticisms of the agreement were: i) no agreement provides legitimate protection against Iran's nuclear ambitions because they can cheat; ii) it was time limited; and iii) it didn't address non-nuclear issues like supporting terrorist proxies in the region or their missile programs.

We can be fairly confident, though, that if this agreement is signed it will suffer the same failures. By definition, you can't solve the first objection through any deal; the only way to solve it is by not having a deal at all and destroying the regime, which would (of course) not be achieved by an agreement with Iran. The second doesn't get solved through any deal either, because Iran can always break the deal at any time in the future - all international agreements and treaties lack a binding term because there's no enforcement mechanism. And there's been absolutely no indication that proxies or missiles are even on the menu for these agreements - and without that, it is (at best) again a deal that exists to try to prevent Iran from moving towards a nuke and not to eliminate Iran as having any regional power.

So, no - the JCPOA was a pretty sold deal which worked to induce Iran away from taking affirmative steps towards getting a nuclear weapon: a combination of economic "carrots" and very formalized enforcement processes to make sure that the terms for getting those "carrots" were abided by. The inherent assumption behind criticism of the deal is the idea that only "sticks" were necessary - that we could achieve the same goals simply by sufficiently threatening Iran rather than offering them economic incentives. Which Trump's Iranian misadventure has proven was completely false: his threats before the war (in February) were unable to get Iran to offer anything better than the JCPOA, and his use of sticks and threats during the war didn't work either. He's back to offering asset releases and sanctions relief in an effort to get some movement on the nuclear program.