I'll start by saying, yes, some customers are rude, arrogant, ignorant, etc.
BUT, customer service has gone to the dogs in the last few years, even before covid it was bad and getting worse.
Not just call centre staff shortages either. In some shops, some staff have treated customers as an inconvenience going back several years - virtually ignoring you, having conversations with other staff, talking on the phone, no hello/goodbye, just grunting the amount you owe, and almost inevitably making mistakes because they're not concentrating (i.e. wrong change, putting items through the till twice etc).
Then we have the Argos/Currys effect where staff don't understand customer right regulations and tell you to contact the supplier when a product is faulty or doesn't work instead of refunding/replacing as required by the law! Or where they refuse to refund something you've bought online when the online T&Cs clearly state items bought online can be returned in store.
As for restaurant staff, I don't care how busy they think they are (often they have time for chats but no time to serve customers), the whole point of eating out is the "experience" and rude/ignorant staff, cold food, wrong orders, etc is simply not acceptable in any way, shape or form. The "best" experience I've had recently was ironically in a very busy Morrisons in-store cafe where the bacon rolls they served were literally all fat and no meat, and the assistant couldn't have been more helpful - agreed straight away to replace, brought out replacements within a few minutes that were much better - all despite clearly being run off her feet at a busy lunchtime!
I'm not even going to elaborate about HMRC - I have to deal with them daily in my job and, again, nothing to do with being busy, most are simply incompetent who havn't a clue what they're doing!
Rather than getting abusive/angry with the shops, restaurants, etc., I simply try to avoid them now, so they lose out in the end, meaning closures, redundancies etc. I buy a lot less than I used to, I eat out a lot less too. It's all just too much hassle. I'd just rather avoid the stress of suffering crap customer service.