Russia has been touting for years that they can do more with less and are developing all these new weapons. The reality is they can't, and they haven't. It's all been a lie and it's now on full display.
They sent in a bunch of conscripts with decades old equipment - and even the more modern equipment is getting destroyed just as easily by anti-tank guided missiles provided by the US and European allies (Javelin, NLAW, etc.). They've touted active protection systems (basically a system that blows up incoming missiles) but those are nowhere to be seen. Instead, they've mounted metal cages with sandbags on top of the turret of tanks to try and stop Javelin missiles which attack the top of the tank where it's the most vulnerable.
The T-14 Armata tank they introduced years ago is nowhere to be seen because they can't actually build them at scale - just a few prototypes to display at a parade. Even T-90s (introduced in 1992) and T-80s (introduced in 1976) are rare and those are decades old. It's mostly T-72s (introduced in 1969).
They're using just a handful of missiles to try and destroy airfields and in one satellite photo (attached) it showed that only 2 out of 6 hit the tarmac. The other 4 hit the dirt next to the runway causing no real damage. An American strike on a similar target would have probably used 15-20 cruise missiles or precision guided bombs precisely targeted at specific targets (fuel facilities, runway intersections, hangars, control tower, etc.). The thing is, Russia has relatively few precision weapons. They're using modern fighters to drop 50-year-old unguided bombs - and having to fly relatively close to do so - putting them at risk from Ukranian anti-aircraft fire.
This is one reason why they're attacking cities with area effect weapons (artillery, rockets, cluster munitions, etc.) they simply don't have enough precision weapons to actually hit specific targets. Also, it's a terror thing to try and demoralize the military and civilians and get them to surrender or face more civilian casualties.