Given the huge amount of additional time and money involved in the in-person method, I think it will be a disaster as far as waiting times are concerned if in-person ceremonies resume. Just the change in process alone will take a long time to smooth out.
The online ceremony itself has only recently gotten better and people have started getting oath within a month to 45 days of DM. Will certain trip up the whole process if they switch back.
The only thing I can think of is the certificates don't need to be mailed out with in-person mode but most IRCC offices are already sending them out within days of the ceremony without any issues.
