I have the same dilemma as you and I wish I could offer helpful words, but I have none.
Some days I think that imageboards and specially kc are very comfy, it's a true internet community, something rare to find, it's nice to read and write in it after a tiresome day, and ask for eletronics reviews or movie recommendations.
In another sense I fully agree with you, it's a huge waste of time, pointless, it's worse than using social media, because in social media at least you are interacting with real people who are somewhat close to you.
I only know that my most productive periods in life where when I didn't use imageboards; and every time there is a world crisis or world happening I read the most retarded and wrong opinions on imageboards.