Usually, I'm the more cynical one about certain things but I'm going to be the positive one this time.

I think it could be a good thing or at the least, not harm anything. Either it will get some to check out more of our books or they will ignore it. No harm done either way IMO. But as I said before, for someone with a huge backlist like me, it's cool to be able to recommend a few books. My backlist is massive and with the way the author pages are now, it will take some time for a reader to scroll through it. That's why I liked the carousel better because you could just look through all the person's books easily.
I can't speak for anyone else but I look through author's books all the time. If it's a new-to-me author I am interested in, I will look at their other work to see what they have written. I do the same with authors I know to keep up with their new releases. So yes, I look at author's catalogs. I would assume many readers do because I know I pick up passive sales for my backlist and many of the books I haven't advertised in years. That means they looked through my catalog at some point and checked out my other work. This is why a backlist is important, because you can keep catching new readers with older books, etc. There is always someone who will be a new reader for you.
As for the follower thing, I don't subscribe to any authors on Amazon. I also am not sure if the recommendations are sent to every author's followers. I doubt it. Probably Amazon picks and chooses. But even if they do send, if someone unfollows you because the recommendations bug them then this is why authors should have a mailing list. I am the first to warn authors about depending on Amazon, Facebook, TikTok, or any other place they don't control as their "meeting place" for their readers. It's important to push the mailing list in your books, website, and wherever. I have my link on my author page. No matter what happens, whether you lose followers on Amazon or anywhere, you will always have your list, which is the most important.
As for will this make Amazon money? I'm sure it will. Everytime we sell a book Amazon makes money. I don't think anyone is naive enough to believe Amazon does things ONLY for the authors' benefit. Of course, they have thought this through and figure it might help them make money but that doesn't mean it can't help authors too.
So right now, I don't see the big deal and will just roll with it. As I said, either it will bring folks a few more sales or borrows or it won't. No biggie and those who don't wanna do it certainly don't have to. But, it's refreshing to see Amazon put up a new feature that's not something you gotta pay for. Lately all they've been worrying about are their ads.