The goal of course is so that they can arrest or threaten employees of these companies, just as China and other similar countries do.
This is so stupid. These firms will probably just say "no" and carry on as before.
Of course not. Google, Facebook, Twitter and Tiktok will almost certainly comply. The actual requirements for presence in Russia seem to be minimal.
The requirements for presence are unspecified by Roskomnadzor, and these companies will basically be putting someone within reach of Russia under threat of imprisonment when they do something Russia doesn't like.