The fear of prosecuting shitlibs is the perception that the prosecution of Trump is what got him elected in '24. To those who see the system as an enemy, Trump getting prosecuted induces a feeling of the "enemy of my enemy is a friend". It lent him anti-establishment cred. Hence the fear of putting the left in this position.
But this is flawed.
The problem is that if you let violence go unchecked, normies aren't going to vote for you, they'll vote for whoever ends the violence. Historically, that's often those responsible for it. If a political party is rioting, killing, destroying property, and engaging in terror, giving them everything they want is a pretty good way to make them stop, in the same way as surrendering to a child ends a tantrum. Normies do not have principles, they have interests, chief among them maintaining a sense of external homeostasis. They will see the chaos, read/hear the justifications for it, get confused, then just vote for whatever makes it stop.
Among the 10 commandments of the syncretic normie religion is "avoid thinking of the past or future, live in the present." This means they don't see the long-term problems which will come from legitimizing political violence, open borders, and cheap labor by the scads.
See the cartel dominance of Mexico and nearly every Communist regime in history for evidence of this principle. Violence works.