The limit is there intentional to discourage comments, and many previous requests to remove it have been declined by SE (e.g. this one). Most comments are not all that useful, lowering the barrier to comment would increase the number of comments, especially from users that don't really know much about the Q&A format. For a new user it isn't obvious when ...
Welcome to 20k, Andrew!
Here's the reference you are looking for: https://skeptics.stackexchange.com/help/deleted-answers
Why and how are some answers deleted?
Answers that do not fundamentally answer the question may be removed. This includes answers that are:
lacking factual references from reputable sources
Regarding your ...
Comments exist exclusively for discussing the posts, and in particular how to improve them, not for giving unreferenced pseudo answers or chit-chatting, or, least of all, having arguments. The StackExchange community mechanics have been designed from the ground up to focus people's participation on two things: asking questions and providing answers. Comments ...
Same thing with the iOS app:
This question has a lot of deleted answers, yet only one shows.
It isn't necessarily a bug, maybe it was made on purpose to not show deleted answers on mobile apps.
You can still see deleted answers from your mobile web browser (mobile version of skeptics.se):