I got a sore throat on holiday in Switzerland earlier this year and assumed that it was either hay fever or a cold but thouight that I test myself when I got home and found myself positive (to my surprise - I've had worse colds). I did wear a mask & sanitise my hands whenever possible. Now that the UK Government no longer issues free covid testing kits I suspect that a lot of people are travelling with covid. Indeed I know several other people who have tested positive on return, with worse symptoms than me, although fortunately nowhere near life threatening.
The problem is that delaying travel for ten days would have cost me a fortune - and given that I don't carry with a smart phone very difficult. I'm actually pleased that I didn't get tested. My thoughts - don't travel if you don't feel well enough to travel, but many with covid will feel ok to travel. Wear a mask & sanitise your hands - is it really a big issue? Remember that vaccines don't stop you catching covid but make it far less severe. People are travelling because they know that they won't be stuck abroad. If that changes its back to skeleon services and layoffs.
That said I believe that it should be a requirement to be vaccinated (unless there are good medical reasons not to be). We've needed vaccines for other diseases in the past and its not stopped us travelling.
One last thought. How much would travel insurance that at the ring of a phone would book you hotels rooms for as long as you test postive, deliver testing kits (and a laptop to keep you amused) to your room & book you on the next flight cost? I suspect quite a lot but that could be what is required if we cannot fly with covid.