You have several potential customers here telling you what they expect to see on a landing page when considering your product. If you’re this stubborn about listening to non-customers who are telling you exactly how to get them into your sales funnel, it gives the impression you would care less about their needs and suggestions regarding the product itself once they become customers.

Listen to your ideal customers, then regurgitate it back to them. If screenshots are not enough, how about a video? Discuss the pain points you’re solving, and show how you solve them. Maybe embed a chat session on the page and let me chat with a bot to feel why it’s better, but do something so I take your product seriously.

No, but you can get a good idea of it. If your UX is as "world class" as you claim then I would expect you'd want to show it off as a main selling point.

Giving me nothing but a bunch of marketing fluff on the home page makes me immediately lose interest.