Just because YOU didn’t know doesn’t mean much. It just means you’re probably not a White Nationalist/Nazi (or maybe it means you are and are just ill informed about the culture and iconography surrounding it ).
It definitely means something to white nationalists.
It’s not about saying Biden is to blame. Trump 100% should have blame.
But the fact that someone else STARTED (or in this case re-started) a bad thing doesn’t mean the next person in power gets a free pass for not working to stop it again.
So it’s perfectly fair to call out Biden for not stopping the bad thing that Trump (re)started.