Are AI writing tools really helpful in SEO perspective?

It depends on how you use them in my opinion. They work best when used to generate outlines and help come up with headlines. I find that this really helps make sure my article really covers all the important questions a potential reader might have. I work at a website builder focused on affiliate marketers/bloggers/SEO, and what we see with our customers is that AI can really help them generate each piece of content faster, but you can't use it to just crank out content without editing. Often times they will generate things that just aren't true or aren't cited properly. We've been advising our users to try and get 50 pieces of content created, only use AI to generate ideas and outlines, and then do a 60/40 split between transactional and informational content, and then make sure your technical SEO is set up and you pass core web vitals.

imo, yes.

Google's user first update has really hit hard.

Of course yes, it makes it a lot easier and faster, but it depends on what you use. I for example do not know how you can already do without the same grammarly or various checks, for example I look through https://studydriver.com/plagiari... whether there is plagiarism in my work or not. I've had it since college when I wrote a lot of essays and had to check everything to get credit.