I think many people said that the city is not exactly important even if it gets captured because the Russian troops are wasting their combat capabilities there for insignificant gains for them.
In that sense, though, the way I see it is that it is useless for the Russians to get it, but it is useful for the UKR forces to hold it for as long as they can or even not lose it at all if this battle is giving the UKR forces a huge advantage.
There is a reason why the UKR forces are defending there with
huge losses on their side; losing that city would make the war a bit unpredictable in that region and beyond because the UKR forces know exactly how to defend there and who knows where the Russians troops will go after that. Will the UKR be able to defend like this in other towns? And, also to retake every Russian-captured village or town, the UKR forces had to fight (almost always) massive battles across the entire front line. I think it would be vital for the UKR forces to not lose any more ground, especially at this stage of the war, considering how everything should be favoring (or supposed to) the UKR forces. Well, if we think or want that the war should be ended soon with UKR having advantage.