Anyone stop doing certain services due to aging or physical

I am mid 50s and changed careers late in life. Kindly folks would call me plump, so I came to plumbing already with aches and pains and their associated limitations. My theory going into it was that I was seeing plenty of lazy young kids getting jobs who had lifted nothing more than a joystick in their lives, so I could certainly do it, plus I brought a lot more common sense and life experience to the table. I am sure that some companies didn’t hire me early on because of age, but enough saw through the drawbacks to give me my start. Maybe they were just desperate for help, but no matter. I made it a point never to expect special treatment, and although I may not have carried as much pipe at a time, I did everything any other apprentice was expected to. At the same time I wasn’t shy about speaking up and asking for help when I really needed it, either from the other guys or my bosses. I was way past that age when I felt I had to be a hero and was afraid to look weak. Usually it was recognized by others before I had to say anything, either the bosses from a liability standpoint or the younger guys just out of decency, or appreciation for me looking out for them when they were making foolish youngster mistakes. Eventually I gravitated to residential service which isn’t as physically taxing as other areas, and with a company that recognizes each individual’s strengths and weaknesses and tries to accommodate for them. No matter your age, no one here is expected to lug a water heater up and down stairs without help, so that is probably the heaviest thing I have to deal with. Same with one piece toilets. Even when doing side jobs I tell them that they need to have an able bodied male helper to help me get those two items in and out or I don’t take the job. I have been booked out 2 to 3 weeks for the past year, and I have plenty of customers ask for me by name, so I must have figured out something right.