Well, a question for the women on the site. I know that many dislike unwanted attention. I was on my last flight leg of my trip, from Narita to Bangkok and a little punchy after a trip from start to finish of about 30 hours with 20 of those in the air. There was a young woman seated ahead of me who was up and around a few times. I noticed she was wearing a nice embroidered dress below the knees with a denim jacket. Add a squash blossom necklace and she would not have been out of place on the Big Rez. Y'know how people flying nowadays dress haphazardly, and I was wearing my ranchwear, nothing fancy (like my embroidered skulls and roses black shirt).
So, you know I am hesitant about approaching people, especially women, and I think I am rarely noticed myself, but I thought her quite handsome in that outfit, so I got up and said "Excuse me, miss." And I got her attention. "I think your outfit is nice, especially with the denim jacket." She pulled down her mask and gave me a smile and was about to say something, but I just held up my hand to indicate I was not expecting a reply and went back to my seat.
Was I out of line with this interaction? I know that people frequently travel in their own bubble and I surprised myself as I rarely do such things.
Overall, I felt your compliment was very fine, based on the information known and given. I mean, you used a polite word, "Miss", said nice and briefer words about her clothing style in a sincere and tactful way, were not asking her to converse with you as she had a mask on and could have thought your hand "up" was just a polite way for you so to say she did not have to take her mask off, risking her to any sickness, and as she may then have felt no pressure to reply, to some stranger.
Also, she would likely have judged your tone of voice, looks, age, and expressions, to see if you were being honest, friendly,offensive, to be feared or flirty. And so I would assume the first two mentioned, if I were like her, if your voice, expressions, posture, age, manner of dress yourself seemed to fit the message given by you to her. For instance, if you were some young guy, with unbuttoned shirt to your navel, and some chain hanging around your neck, used inappropriate language and tone, and had eyes sizing her up, yeah, that could be a problem.
But, yeah, I thought what you did showed more kindness, sincerity and politeness than not, knowing many women can prefer others at least think of their attire sometimes in a fashionable way, and as she may have dressed for a more formal occasion. Some women, however, depending on their personality and mindset at the time could have preferred more space, or have been at least a little surprised by what you said or did, but sometimes it's OK to risk such comment to show how we really feel, if some feeling like that was genuine, coming from your heart, with no ill will intended or anything expected in return.
Personally, I could never though make a habit of doing something nice like that on my end, but just if a rarer such occurrence was present that I felt more justified that, or if I felt the other would definitely be receptive to that. It would be hard for me anyway to initiate appropriate such comments anyway, and as I am not the type to initiate such nice comments about others' physical appearance--men or female- being more introverted and fearful of rejection there. I admit my focus often has been more on others' personalities or actions, and I would take more risks there in stating my nicer feelings there, for those rarer times.
In this age where harassment claims can be given in the wink of an eye, and many can still seem more hesitant to talk to strangers, I find the safer approach for me is to just focus on being polite and somewhat formal, factual, brief, and less loose with my words, but showing compliments too, if a very nice deed or actions was given. Like, my wife thought that mug given to her by your wife in person at our place a couple of days ago was an awesome expression of friendliness showing her kindness! She loved that message on it too, and it gave her a smile and calmness and the needed energy to proceed with the meeting.
How rare is it that "by chance" two on the forum who post somewhat regularly or are known would have some family members meet for an hour, not knowing in advance of that and not expecting such. This is a small world after all. Props to your wife for the important work she does helping others!