Perhaps you do not know the difference between a blitz and a formal siege. It is clear that they ran troops down the road thinking that they could take Kyiv with little resistance. If their objective was not Kyiv why then did they attack it from both the north and the east? I will concede that perhaps with their overwhelming superiority of artillery that they might be able to level and take Kyiv. But this would have been a protracted and bloody affair (see Stalingrad), the precise opposite of a blitz.
The Russian may well win in the end, but for now they tried to capture Kyiv and failed.
“If their objective was not Kyiv why then did they attack it from both the north and the east?”
If you mean Kiev, it was a move repeated dozens of times on the eastern front in WWII. These thrusts made Kiev have to commit forces there instead of rushing everything to the Donbass. It also made potentially encircled nazi militias in the east have to look behind or risk entrapment...as also happened dozens of times in WWII.
In short, to Kiev it looked like an attack everywhere, at once. In the vaporlock of their minds, the main Russian force taking the Donbass was not facing the whole Uke military at once.