Critique my business ideas

So I have some business ideas that I would like to confront to you in order to have feedback. The point is to give me your completely honest opinion and try to find some potential problems.

1 - Digital marketing automation for green ecommerce stores

Marketing has always been a problem for everyone in business more particularly for niche businesses. It's tough for them because people who will buy their product are generally harder to find. Also these products are way more expensive than other so it may be clever for them to focus more on marketing. Since the green and sustainable industry is growing at a very fast rate such as AI, I would like to hear your opinion on the idea of automating marketing for these type of businesses.

2 - AI Mental Health platform

The mental health issues will gain more and more importance in the future. We now live in a world that isn't as safe as before and with the rise of social media we can predict that mental health issues will be more frequent especially for young people. PH, Instagram, Tiktok all of these are just bad for everyone and so an AI mental health plateform where people can chat with AI, discuss in anonymous forums and use integrated tools to reduce screen time and manage addiction I think would be a good idea. I haven't really thought about how to make money but as I write I was thinking about either a freemium model or integrate products from stores and kind of get affiliation, getting money when people buy the product.

3 - A car enthusiast website

Everyday around 5000 millionaires are created so obviously the high end car industry is growing at a fairly fast rate. My idea would be to create a network where people would pay to ride in a supercar. There would be a map where people would look for cars in their area and chat with the owner basically.

4 - Marketing agency for real estate agents

This is self explanatory. Common pain points include managing client communication, nurturing leads, following up on inquiries, and staying top-of-mind with potential buyers and sellers. Effective email automation can help with sending personalized follow-ups, reminders, newsletters, and market updates. It would be a subscription based business basically.