You can always trade in by mail. I just did it for my M1 Air. I still need to drop it off at UPS, but no driving to the mall, parking, and waiting in line.
This is also why I buy almost everything from Amazon. Their returns process is worlds ahead of every one else. It also doesn't hurt that drop-offs are at grocery stores.
My problem is I initially had a trade in by mail in process. But since I have to walk by the apple store daily on my way to work, it was one of those rare moments where mail was actually less convenient. And I was concerned about the mail in return contractor deciding the phone is worthless (it happens).
Apple made me call to cancel the trade in, then said they could do it in store. They could not, not then, not an hour later, not days later.
Internet and apple store employees said it should be fine. I guess they don't make geniuses like they used to.