This is what stopped me from signing up as well.

Weird table. I use Foot which is pretty fucking fast and does everything I need except panes so I might check this one out.

Yes, this is what spoilt brats do. There is no masterplan here.

They probably still have usernames, phone numbers and access logs with IP adresses even though the chats are encrypted.

Telegram never or rarely cooperates with authorities in investigations into terrorism, child abuse, drug trafficking, weapons marketplaces, etc. This is probably the main reason they arrested the guy.