To start by quickly answering the second question: vanishingly few vegan leathers use recycled plastic. Polyurethane is notoriously difficult to recycle, and recycled polyurethane is generally so low quality that it cannot be used to make clothing. Your vegan leather jacket is not only made from plastic; it is almost certainly made from new plastic.
So, bluntly, I don't think that it is impossible that someday there will be vegan leather that doesn't involve plastic. I think that we've made incredible progress in the space of lab-grown meats, and from there, lab-grown skin seems entirely feasible. We may even have lab-grown leather within our lifetimes, and I'm excited about what that scientific progress means, not only for textiles, but for bio-engineering more broadly, and for medicine. It's very cool stuff, genuinely!
But, getting excited about scientific advancement is very different from being sold a bill of goods. There are so many vegan leathers on the market that are just greenwashed plastic that at this point, it is genuinely irresponsible to hear about a new one and start hyping it up without doing any due diligence. I'd love it if there really were products made out of apple waste or pineapple leaves or cork or whatever which had the properties of real leather. That would be incredible! Even aside from any reasons for avoiding animal leather, imagine if all that plant waste could be repurposed into clothing and upholstery. Imagine if all of the uses for pleather were replaced overnight with a sustainable, biodegradable alternative. It would be a wonderful advance, and I'd be shouting about it from the rooftops!
The only problem is? Right now it's a lie.
Cactus leather and pineapple leather and mushroom leather and the like aren't wonder-materials. They are a marketing scam, meant to trick you into buying overpriced plastic as a "green" alternative material.
I've said it before in a hundred other contexts, and I'll probably say it again a thousand more times before I die:
Getting scammed isn't praxis.
I'd love it if these claims were true. I want them to be true. And I will never, ever share or promote them, because wanting a lie to be true doesn't make it so.
Every vegan leather currently on the market is greenwashed plastic, and you should treat every new vegan leather that you see as "plastic until proven otherwise."