Yes and No. a few points i've seen raised that seem valid.
1) Ukraine have very little negotiation power if/when negotations start. if they hold Russian land then they have something to trade.
2) cutting off supply lines. by attacking where they have they have cut off one of the main supply routes to the Kharkiv front.
3) Morale, with Russia pushing ahead in places its hitting Morale of the Ukraine forces, this is a much needed win.
4) Ukraine have to defend there whole border so have stretched forces across the whole border, Russia believed they didn't have to defend theres so have moved the vast majority of there troops to attack small fronts allowing them to push hard against Ukraine. By doing this Russia will have to move significant forces around to defend there whole border and therefore weakening any fronts. 1 Attack like this may not shift that much in terms of Russian forces, If Ukraine do it again in another area then the need to defence there whole border really kicks in.