I’m doubtful they would cancel at this point (barring something even more unexpected than the recent surge) but could see them doing more corrals and maybe more staggered starts and such. Unless the trajectory goes crazy, I think the medical facilities are more prepared, they have refined treatment methods some, and the severity of a large amount of cases is much less when it comes to those who test positive but are either vaccinated or have already had it before. According to the stats on world one tee.com, cases have obviously skyrocketed, but, while deaths have increased, they haven’t increased anywhere close to the same rate.
It’s all pretty speculative at this point, but I think there are comparatively less unknowns for medical personnel than last year and less likelihood the hospitals will be overwhelmed again, so I’m cautiously optimistic. And I think Disney is more comfortable with people congregating outside while targeting masking indoors (as exhibited by their recent modification of their masking policy to not require them in outdoor queues).