Elder Scrolls Online isn't made by Bethesda it's made by Zenimax Online but Bethesda is the publisher. Bethesda can't make online games just look at Fallout 76.
Yes Fallout 76 had issues at launch, but so did FF14, so much so that they had to pretty much revamp the entire game.
Fallout 76 is well supported and the most jarring issues fixed. Almost 14 mill players is not a bad number to sustain a game that was proclaimed dead a short while after launch.
Hopefully it will die dead so they can put all their focus on TES VI.