Russia has proven that despite its massive military, it cannot do combined arms warfare. It can’t coordinate its infantry, armour and artillery but most importantly, it cannot achieve air superiority over the battle space. It can achieve short term local air superiority but only short term .
Nato and particularly America have proved that they are able to do this at Will against enemies even if they are equipped with reasonable air defence missiles. Once you control the airspace, you control the battlefield.
NATO’s armies are much smaller but they are much better trained and they can do combined arms operations. NATO puts faith in its battlefield commanders and allows them to take the initiative. Russian forces are massively inflexible, if the plan doesn’t work, they bog down and wait for orders from on high, even if the solution is obvious.
I wouldn’t say they are no threat to NATO but they aren’t the threat we once thought they were. Their organisations are institutionally corrupt to the point where a large portion of their military is not effective because money for training and equipment has been siphoned off to build dachas for their generals.
The other military threat is China and I suspect that they aren’t much better than the Russians. They have the same doctrines, equipment and there is widespread corruption in their society. They have even less combat experience. They are also surrounded by sea that the Americans control. America has 16 aircraft carriers and China has 1.
That leaves nuclear weapons. Can’t worry about them, there is nothing we can do about them.