They can do, BUT they have to be supported by a lot of infantry presence.
Do you see in Kiev a lot of Russian infantry to support such a thing?
NATO is giving anti-tank weapons like candy
Javelins are more suited to open warfare. They aren't nearly as useful in urban combat. Most Russian losses seem to be from logistics and vehicles breaking down rather than javelins. I doubt they have anywhere near enough in Kiev to make a difference.
Ukraine's defence of Kiev against tanks seems to be to hand out Molotov cocktails to babuskas. If they were smart they would have at least given the thousands of Soviet era HEAT rounds to use as IEDs.