Europe has no way to project meaningful force into the west Pacific. I'm not exaggerating when I say their flotillas will be ASBM fodder before they even reach the AO. The most they will do is write a flaccid letter condemning China for destabilizing the region.
Russia is serving its purpose well by maintaining a threat vector and bleeding European resources. It's in China's interest that the war in Ukraine goes on for as long as possible.
The European gambit is to attack that which the opponent must protect try to force America to commit to the defence of Europe, thereby scuttling their plans of a war in Asia at the same time, as not even Trump would be delusional enough to think he can win a two front war against China and Russia.
Even if America did go all in on a two front war, the European theatre would be a useful means of draining American resources and combat power from the Pacific. The bet is that whatever percentage of combat and industrial power China needs to invest in the west to put pressure on the European theatre would cost America a greater (potentially multiple times greater) percentage of their military and industrial power to balance off and avoid a total collapse of their European theatre.
The broader strategic calculus is that if Europe is going to commit to America’s fight no matter what, it’s better to strike at them sooner rather than later. Europe does possess sizeable industrial and populations inheritances. If given time to arm up and dig in, it would be a much more costly and difficult job to take them out than to strike at them immediately.
Additionally, much of Europe’s MIC and industrial production are or can be easily plugged in to supplement American MIC production. Even without access to new RE shipments from China, they will have sufficient consumer and dual use products in circulation that stripping RE from consumer products could potentially become a viable means of feeding western MIC production needs, at least in the short term for some advanced weapons. Attacking them early deprives America of that industrial capability and potential recycled RE pool to support and supply their own MIC production.
Finally, as the age old maxim goes that logistics is fundamental to long term military total victory. Taking Europe allows China and Russia to not only control the Eurasia world island, it also allows them to easily deny America access to resources in the ME and even Africa. Additionally, taking Europe allows China and Russia to threaten CONUS from both oceans and in both coasts. That will significantly weaken their naval and air defences compared to being able to rely on Europe as their secure rear and focus the lion share of their forces to the Pacific.
Sure there are risks to proactively opening up a new front and taking on a significant power, but those risks are massively mitigated by Europe’s puny standing military strengths and the near inevitability of them jumping in on America’s side no matter what given how thoroughly America has infiltrated and compromised their civilian, military, intelligence, media and corporate leaderships.
Finally, opening up the European theatre first opens the possibility of there being no significant military combat in Asia. It might be a modest or even slim chance, but given the potential monumental benefits, it’s well worth the gamble.