When we went on a cruise I kept to very low carbing (imposs to say whether I stayed keto, since I couldn’t do the proper calcs and I didn’t have a ketone meter with me), but it was surprisingly easy to avoid the big carbs.
What was interesting was that while I gained no weight whatsoever, and had no obvious digestive, sleep or other consequences, I did get the old joint pains back, and my energy levels dipped tremendously.
Which led to me deciding that I would have enjoyed the cruise MORE if I had been more strict with my eating. Yes, it would have been a minor inconvenience at the table, but it would have meant I enjoyed the trips, stairs, and other activities with a sharper brain, more endurance and less discomfort.
Each to their own, I guess.