As far as I can see every “tree surgeon” will happily cut down every tree and say it was diseased, or will mutilate it so it looks sad and spoiled for the rest of its life
That’s simply not true, watermeadow.
It’s true that sometimes trees are spoiled by inexpert hacking, but a properly qualified tree surgeon, as anno says, can shape a tree and make it even more beautiful.
I have several trees in my garden and for years was very reluctant to do anything to them.
Then a tree surgeon was recommended to me and when he had finished you couldn’t tell anything had been done to them, except that they had a better, more contained shape.