We cruised the Wonder to Alaska in 2018, so I can't address Covid protocols. The ship docks a short distance away (walkable, but there's also a free looping shuttle) from a main tourist area of the town that has many vendors of tours available, as well as the Mt. Roberts Tramway, Tracy's Crab Shack, etc. At this tourist area, you can simply walk up to a vendor and buy bus transfers to Mendenhall Glacier (it was about $90 for the two of us, and they take credit cards). These are buses that make looping round trips, so that you can get on and off at the time of your choice. That's what we bought. It was an old school bus, not terribly comfortable but okay. I don't remember seeing any nice coach buses doing the loop. The bus dropped us off at Mendenhall, and said how often the bus would return for pick-ups (probably every 30 minutes or so). This was great, as we were free to spend exactly the amount of time we wanted exploring the glacier, and then could leave when we felt like it, and we didn't have to stick with a group. No stress, no hassle. We had plenty of time to go back to the main tourist area afterwards, have lunch at Tracy's Crab Shack, and also take the Mt. Roberts Tramway and explore that, as well.
