People don't move from platforms, they drift away naturally.
I didn't move away from slashdot, I just found reddit suited my needs and naturally visited the site less and less.
and then, I didn't move from reddit to HN, I just used reddit less and less until I realized HN fit my niche more.
I still have my slashdot account, but it's been unused since 2014
with reddit, I deleted my account in a fit of depression... but hilariously I still visit the site regularly (much easier to track my various entertainments there), i just no longer comment there.
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I don't user Instagram because, I just don't... get it? Too old for it.
I deleted Facebook when I realized all my extended family was on it and I just didn't to see them on social media.
Who knows how I'll fare with Twitter. I rarely tweet (honestly, because I am afraid of speaking on the platform, public speech is dangerous in my country) but I regularly use it, because where else will I get my instant updates?
So I will go where the updates are.