Why do you think an entire continent with multiple and (sometimes even conflicting with each other) culture, priorities, national interest would do that? EU is an economic union. Not a federation like US
European support started out slow, but has ramped up as the US has backed away.
Germany will spend 20% of it's federal budget on military in 2027, planning to increase that to 30% by 2030. "We cannot defend ourselves against Putin with a balanced budget".
What would come next after Ukraine may be the Baltic states or Poland.
According to your YouTube sources? NATO has nothing to do with Ukraine. NATO countries can defend themselves if one of those countries actually are being attacked. That happened in 9/11 and NATO countries supporting militarily the US wars that preceded.
They have no such obligation towards Ukraine.
There is if you ever want to negotiate a nuclear arms-control deal again. None of this would be an issue if Ukraine had kept their nukes.