Because continuing bringing outland immigrants while local people experience job and income losses is not a smart decision in a political sense.
Also, the government has spent tremendous amount of money on aid and there is going to a process of cutting costs and expenses to lower the deficit, therefore immigration might also lose its share of the federal budget.
Right now, internal matters are the key focus of every government in every country. No one cares about potential outland immigrants.
Travel restrictions have little to do with ITAs in my opinion. Travel restrictions will be eased sooner or later and with the current processing times there is a high chance that travel restrictions would be lifted before the first outland immigrant, who would have applied during COVID-19 pandemic, obtained his/her COPR. Also, the government has no issues with extending both COPR validity and requests, but it still decided not to invite FSW candidates, so there might be a different reason for that.