In a way you are right, the army in particular has moved away from mass armour peer on peer and moved to counter insurgency warfare.
Not investing and cutting the artillery, replacing challenger 2 with jackals and thier open top roll cages is just a LOL.
It's funny - given the UK's arms industry is one of the best globally. At this rate we'll be fighting our own arms sold to other countries as they go to war against out interests.
Putin's army, when at the advertised numbers, is designed to send a signal of iron force strength. It doesn't need to be clever, just pure numbers in a Blitzkrieg - that one hopes would stop and not roll into other ex-russian countries.
Western tactics have been simply identify and target key points thus rendering the enemy forces ineffective then dropping bombs with air power.
I suspect that will be almost the same tactic that the Russians use:
1. Build up a mass force on the boarder - that's the threat and hope that things buckle psychologically.
2. identify and pinpoint key points - through cyberwarfare, insurgency and recon.
3. Attack key points - through cyber, then where needed through small teams and dropping munitions from the air but with less precision needed. This reduces the communications channels and reduces effectiveness.
4. Sweep up with a back force of armour - it doesn't need to be massive, however given the time to react by the west, Putin may use large amounts to simply speed the operation.
I don't think the west will advocate the attack/capture of Russian land elsewhere on the boarders unless russia goes full rolling Blitzkrieg, which they won't - unless China wants to attack Taiwan at that point.
Russia, although large, has the disadvantage of large borders - if it commits forces of people then that costs. Although he has gold reserves etc it's easier for him to weaken countries economically through their reliance on Russian fossil fuels with espionage and cyber being more direct means.
I do think that the EU countries and the UK have, in the last 20-40 years, been rather lapse in their long term understanding of Russia and China. However that's easy to say with hindsight.