Yes, Russia will kill Ukrainian civilians either way, true that, but I wouldn't want something like this leading to further escalation by Russia or a drop in support by the US, last I checked the US was rather adamant about not wanting their weapons used in an aggressive manner on Russian soil.
As for Russian escalation, having their own soil attacked could be used as a powerful motivational tool for Putin. Their special military operation could escalate into an war of defense of the motherland.
They already claim the "annexed" regions as Russia, including Crimea. All of which have been attacked successfully. Hell, Kherson was abandoned and the Russian media was confused if they could even talk about it because of the laws about "defamation" on the books now. Let's not forget someone flew an explosive drone into the Kremlin earlier this month which even Putin doesn't seem to care much about, and last year someone blew up the Nordstream. Putin heavily implied the Brits did it and....apparently he isn't that mad about it considering he just kind of shook his fist at London, made one of many imponent nuke threats and then just kinda got bored of the whole thing or something.
The problem being that Putin keeps talking Red Lines and then nothing really changes. Hell, Putin apparently didn't bother with the Nuclear Threat over Ukraine getting F16s. Now there's talk that Sweden might provide Gripens as well.
It's possible he's realized he has no capability to escalate without pulling out the nukes and he already knows that's gonna bring the hammer down if he does. These raids seem to be particularly embarrassing because it's showing not only can't Russia win a victory beyond a bloody 10 month assault to take Bakhmut, they can't even properly prevent rebels from running back and forth across the border. Even worse, now they have to figure out how keep reinforcing the front lines but also find forces to protect their towns near the border.
I'm not privy to their force distribution but I suspect they're getting stretched very thin. They have to know Ukraine is preparing a counterattack at any time so pulling anything off the line could result in another Kharkiv Rout or Ensure there's no way to respond and plug holes in the line.
I've been saying it for a while now. You can't just burn through tanks and vehicles with impunity. Eventually you're gonna find yourself with no reserves and I suspect that's what's going on here. Russia is very likely running dangerously low on operational reserves. That's why the parade looked so sad. That's why they can't seem to prevent raiders from running across the border to belograd. Pretty much everything that can be committed probably already is and throwing more mobliks into the mix doesn't seem to be doing much.