And if you do ask, how would the waitors and waitresses react?
I don't know. I've never asked for a service charge to be removed.
Something similar has only happened twice in my almost three years in the UK.
First time around, this was way back in 2018, I was in a hotel bar and it was busy and it took a while for them to take my order. When a Chad waiter came around to take it, I said I was kind of disappointed that it took them this long to get to me. The Chad and a femoid manager conferred and said that they would let me have the drink (it was like a £25 cocktail too) and another drink on the house. I immediately felt bad because I'm not really the type of person who complains, and then I said I could still pay and that I should've expected service to be slower on a busy night. Then he insisted that the drink was on the house, then I insisted on tipping him, and then he insisted that I not. Anyways I declined his offer of a second free drink since I had somewhere to be, and the foid manager gave me her card, blah blah blah. I became a semi-regular after that (when it wasn't term time), he remembered my name every time I saw him. Unfortunately he left to work someplace else and I haven't been there in a while.
Second time, like a year ago, I had a function to attend and stopped by at a nearby hotel in Knightsbridge for breakfast. Service was slow and I really couldn't be late for the event, so I tried to discreetly flag down a server to pay my bill. Finally, I walked out and told the maitre d' that I hadn't actually paid but I said I couldn't find anyone and really needed to leave. She was apoplectic, apologized, immediately brought up a credit card machine and waived the service charge. Then she offered to arrange a car, I said no because the embassy was just a few minutes' walk away.