i love Tiktok, i've been on it since 2020 (A lockdown discorvery) and i spend most evenings on there. Its funny, educational, entertaining and heartwarming. Its a good place to learn, to hear world news, and peoples views.
If you're not using it right, it will rot your brain, but to me, as someone with ADHD and a thirst for learning, its a gold mine.
Without it i'd miss all the animal rescues, farms, comedians, cleaning, rug washing, dog groomers, cat, horse, dog accounts, news.. and some pretty important mental health support.. like KC Davies "Strugglecare" that got me through some difficult times.
I've picked up new books, new hobbies, and new music on there.
The only 'brain rot' is not curating it to be what you need from it.