There's some of that. But I think the border is still the issue. A lot of fans came from Fort Erie, Niagara Falls and St Catherine's. The testing requirement adds a hundred dollars or more to a trip to Buffalo.
Then the last part is what @PASabreFancalled the "Chet & Muffy" contingent. The people who come more for a night out then a hockey game. All they heard was the team is bad now.
Of course there are advantages to small crowds. Lots of room, no lines, and you also get more real hockey fans. It's nice hearing a cheer on TV from people who understand what they are seeing