While I'm not surprised, I agree with others than masking preference could make for an awkward trip. Yes, those that are more comfortable with masks should be fine asking others to mask up, but be prepared for them to (hopefully) politely say no just as often as they politely say yes. The CDC is saying they are not putting others at risk, so I do expect folks to get defensive about being asked to put it on. Personally (and yes, we all feel varying levels of comfort right now, and that's ok) I'm comfortable with the air flow level in the cabin that I won't be asking people to mask up, especially with the CDC telling me I'm safe from others, and they are safe from me, because I'm vaccinated. I do think this decision will make some avoid the gondolas all together for the time being.
Everyone needs to do what is best for them, but I don't think it's fair too call someone rude for politely disregarding a request to mask up. The federal guidance is telling them it's safe for both themselves and others, and it doesn't make them rude to follow it. Personally, I think the most polite thing at the moment is just to quietly accept that some follow the guidance and some prefer a more conservative approach, but neither are wrong. You may get stuck together for a short period of time. Demanding the other party do it your way isn't fair. I just don't think either side is inherently more or less rude than the other.
** PS: Because it's an attraction aren't they required to mask up anyways? My reply (I should NOT speak to others before coffee dangit) is geared towards if they COULD be taken off while on the gondola. Remembering they're required to be worn, I feel reminding another party to mask up is fair, but be prepared for them to not be polite about it. I'd love to think they would be kind, realize oh, we forgot, and be done with it.