Corruption and incompetence is widespread in the Russian police force. I doubt they will get into trouble for this.

If they keep threatening everyone who voices their opinion like this, won't Russia face an exodus of their intellectual elite?

In fact, Russian 'intellectual elite' lives a cross-border life for decades. Markets for their work are mostly abroad, their cultural interests are abroad as well, Russia is just a sort of a big 'commuter town' or 'sleeping block' in Russian terms. They are not tied to Russia never financially not emotionally, and for all practical purposes can be treated as emigrants except they are still Russian tax residents (you will be surprised, but Russia has an exceptionally light taxation for self-employed).

They already have.

Whom are you thinking of that left after the fall of the USSR in 1991? I do not mean to challenge you, but others will, so I would like some details.

Anecdotally, I've met many well-educated Russians who left in the mid-90s. I think, though, this was mostly due to fear for personal safety and a sense that their country was in a unrecoverable tailspin.

their guilt/punishment is a separate legal case, Kasparov said he is planning to sue the arresting officers in court