This question is a duplicate of a question asked four years ago, which does not seem to have been followed up. I apologise if I'm violating the norms here by asking it again, but it seems to me the issue is better addressed by a new discussion given that the SE galaxy has changed somewhat in that time.
It can be very frustrating attempting to read a chain of comments, only to realise that some were in reply to now-hidden comments. Especially due to the placement of the 'show hidden comments' text (ie at the bottom, reached once one has finished trying to read the chain), this leads to a confusing and irritating experience. Further it is then frustrating revealing the hidden comments and figuring out where they fit into the chain you've already read.
It would seem quite doable to enable an option on one's account to show hidden comments by default (or to hide all comments by default, as quite a few people seem to want). Is there any strong reason not to do this? (Or, I suppose, am I an outlier in wanting this?)