Well unlike most other gimmicks yanks wank, night vision devices (i.e. thermals) are actually quite useful. Thing is, Russian forces have them. Both in personal variety and on tech (such as drones)
Ukraine forces literally used Ukraine citizens as hostages and shields during the first few months, keeping them locked in basements under their fortifications and not letting them leave on the Russian free passage routes
Russia had an agreement where they had daily ceasefires and a safe evacuation route, and they held it open for weeks and nobody went down them. Ukraine forbade civilians from evacuating and escaping, and then whined and complained about civilians being attacks when Russia sieged mariupol
That's been their MO for years now, they are so used to invading countries with no more organized resistance than some guerilla fighters (who usually end up beating them back anyway), they can't help but underestimate The Bad Guys as being technologically inferior to them. The idea of fighting someone that has most of, if not all of, the same capabilities as you is absolutely foreign to them.
Even after over a year of evidence being provided to the contrary, they simply cannot believe it.