Public transport is very much a no go now but not for the reasons I think you have in mind.

Between the strikes, the staffing levels, the out of date rolling stock and the lack of investment I'm surprised any buses and trains run at all.
However, that is not what you meant.
You may not have noticed but Covid didn't go anywhere; or rather it went everywhere but the media got bored of the hype, the government found other things to spend our money on like war and very quietly the advice about how we should deal with Covid changed to something like what the Swedish did at the begining of the crisis; something our wonderfull politicians condemed with much self rightous crap at the time.
I've been traveling every day, some times twice a day for the last eighteen months to and from the allotments on public transport while Covid spread and mutated. I've got quite good at spotting the sick on the buses and trains and take the necessary action to avoid close contact. Many it seems believe that if they've had the jabs they can no longer contract Covid. My sister who would present herself as an intelligent person is one such. What the vaccinations do, probably in most cases, is reduce the severity of the infection. What many people it seems do not understand is you are still infectious, jabs or no jabs should you contract the disease.
My sister and her husband have been a two person super spreader event; not because they contracted Covid but because they are ignorant.
What I've learnd is fresh air and freedom of movement will help keep me well and the people I have to try to prevent from killing me are friends and family, who many, despite the vast amount of information on the subject want to rush around hugging and kissing everyone.
So, yup, I'm still using public transport. I wear a mask and choose off peak travel times when possible. I wash my hands a lot, sit by open windows if possible and in general try to keep a sensible distances from other people.
The best place for doing that is at the allotments.