This is a superficial take and your logic makes sense at that level.
But when you dive deeper into the situation you’ll understand that Russian got the concessions they wanted under Trump so there was no need for them to do anything. Under Biden, Russia was not getting the concessions they wanted. They were legitimately afraid that Biden would force Ukraine into NATO so they invaded to prevent that from occurring.
Russia was much more afraid of a Biden administration because they felt their power would weaken. Under Trump, Russia feels much more powerful. It certainly wasn’t an issue that they felt Trump would engage Russia militarily.
Thanks, that was a GREAT laugh.
Russia was afraid of Biden! That had to be it.