Changed the oil in our main daily driver, probably was a bit earlier than strictly necessary but it was past the service mileage stipulated in the manual and it’s above freezing finally. Managed to not make a mess and didn’t run into any issues. Even torqued the drain plug to within spec. Then got it washed to get rid of the salt crust from the past few weeks and wash out any oil drips from the filter the got on top of the plastic air guard.
You probably still can if you buy conventional oil but most cars require synthetic and the cost savings isn’t worth the risk and worse protection.