they are also wasting a much more precious resource than planes, pilots.

And the most precious resource of all, the purchasing power of their own currency.

Unfortunately this is being ameliorated by us paying them hand over fist for their oil and gas.

That is already gone.

energy?

I think the parent means that Russia's biggest income source is oil and gas. Now that he demonstrated to it's biggest customer (Europe) just how problematic this is, the demand is not going to go up.

Other than in the US where russian Oil is like 3% of the used oil and russian gas is basically not used, in Europe no russian gas means cold houses and problems in the industry.

Russia borders something like sixteen different countries. They have to keep in mind all of those other avenues of potential attacks which might account for some amount of holding back.

Nobody is going to "attack" Russia. Out of those sixteen neighbors there is exactly one, China, which could even begin to contemplate taking on Russia in a land war. (And they still would not, because nukes.)

On the other hand, China could try and strongarm Russia into concessions (no idea which ones) while politely performing military exercises on the other side of an undefended border.

Similarly, if NATO starts politely performing military exercises near any of the other borders of Russia, Russia needs to be able to demonstrate that they have an army guarding said border.

I'm somewhat doubtful that Russia is keeping their best equipment in reserve in case checks notes Georgia or Finland invade them.

While there has been some drunken bar-talk about retaking Karelia and re-establishing the pre-WW2 borders, It's not likely Finland will attack Russia.

It's more likely the russians are a) incompetent, or b) saving the bulk of the air force for a potential escalation of the current hostilities. One does not have to exclude the other.