They own a modern, paid-off arena (and all attendant revenue streams) that was financed when interest rates were around 0.5% - and if that weren't enough, the mortgage was paid by government tax breaks and refunds (to the tune of about $12M/year). They also operate a franchise in a hard-cap pro sports league with a guaranteed 50-50 player/owner revenue split and significant leaguewide revenue sharing (playoffs, merch, national TV deals, etc.). On top of all that, the co-owner of TNSE is worth billions and seems quite invested in the idea of NHL hockey in Winnipeg. To top it all off, the team is worth 10 times what they paid for it in 2011 (Sens just sold for $950M USD = $1.25B CAD).
They made a lot of hay while the sun was shining, and with their current ownership structure and facilities and conditions, they can certainly weather some empty seats.
Things are completely different - in many ways, totally opposite - to the conditions in the early/mid 90s that led to the original Jets franchise relocation.