Can AI read substack.com?

I could not fetch this site's homepage, so this check is incomplete.

AI search crawlers can reach it
OAI-SearchBot and PerplexityBot are allowed.
?Homepage is readable by crawlers
Could not fetch the homepage (429), so I cannot tell how much text a crawler would get.
Has an llms.txt
No /llms.txt. It is an emerging, optional convention, not required to be cited today. You can generate one at https://ai-visibility.lastminutedealshq.com/llms-txt

I could not fetch this site's homepage, so I cannot tell whether it sends readable text.

Check your own site or see the crawler census.