(part 2 of question)
there were two times when two people from the fandom wrote to me under the post, but when I asked them a simple question trying to start communication with them, they didn’t answer anything, as if they thought that I would supply them with content and not tell them anything, or that I would be a fan of their content who didn’t will tell them nothing. maybe people on the Internet in general have become worse or has it always been like this? or maybe people got worse everywhere? (2)

I first joined Tumblr around 2013 or so and I think internet culture in general (on Tumblr and elsewhere) was very different back then. I’ve unfortunately noticed more of a trend in fandoms where content creators are less looking for friends and more looking for an audience. It’s tough to make friends this way when the other person’s primarily goal is getting “engagement” on their art or whatever it is that they create. I think it’s natural to want to get recognition for the hard work one puts into their craft (I know it’s something I definitely crave), but I dislike how more people are starting to view interactions with others through the lens of “this is a potential fan” and less through the lens of “this is a potential new friend”. Maybe I’m cynical because I’ve had a (former) friend like this who basically went into the dynamic with the goal of making me a member of their fanbase (and exploiting my hard work in my craft to elevate the quality of theirs through collaborations), but… yeah, it happens more frequently these days.

If I had to take a guess, I’d say the algorithmic nature of social media platforms has contributed to this a lot. People are much more focused on getting their work to be successful these days, while the focus a decade ago was much more on connecting with others in a chill, community based around meeting people who liked similar stuff.

Tumblr is actually a bit better in this respect, as it doesn’t focus as heavily on an algorithm as, say, Twitter or Instagram (the latter of which I despise tbh). But even so, I think interaction is much easier on Twitter because it’s more normal to comment, whereas most people on Tumblr communicate either directly through DMs or indirectly through tags on reblogs. There’s less of a middle ground because for some reason, people don’t like commenting on posts or even reblogging with their own thoughts. This could be because of fear of modifying someone else’s post, but it sadly leads to it being tougher to talk to people on Tumblr unless you DM. Tumblr for me is more a place where I just keep track of posts I like and occasionally post some of my own, but as for interacting with others, I don’t think it’s the ideal place. Twitter is more conducive to that despite its… current downward slope in quality 😅

If I had to give advice for making friends on Tumblr though, starting off with more subtle hints towards wanting to be friends could help rather than just DMing out of the blue. Reblog their stuff, leave your thoughts and compliments in the tags (that I can assure you they’ll almost certainly read), and just engage with their blog in a way that indicates that you find them interesting. They may check out your blog and realize by the content you post that you two have stuff in common, and might even follow you back. Most of my mutuals/friendships that started on Tumblr are kind of limited to this liking, reblogging, and commenting-in-tags dynamic, but I have been lucky enough to have some progress past that and lead to regular DMs and even friendships that have lasted a couple of years.

Sorry for the late response on this and hope it answered your question!