The margin on a VW isn't as high and costs significantly less on average than Lexus, so independent dealerships selling VWs have to operate on volume instead of long-term reputation and relationship building. The VW shops will be nice but don't have the time or budget for all the extra.
"Everything you described depends 100% on the individual dealership not on the brand."
This isn't the case. Just like different luxury-leaning domestic brands in Europe have levels of corporate ownership or incentive to provide certain services, leading Lexus also has what I assume is an incentive program for dealerships to offer different levels of lush care: https://www.lexus.com/guest-experience.
There will be outliers but the trends and reputations exist for often explicit reasons.
I imagine if Toyota is going around building their Lexus brand around "concierge" level service, they could attach bonuses to this metric—maybe weight the bonus more heavily in that direction than they do for their Toyota brand—and punish dealerships that disappoint their customers.
Then again, a lot of dealerships are owned by huge dealer groups now, so the power balance isn't always tilted toward the manufacturer.
Lexus of Austin would have owners lined up out to the street every morning to get routine services done. The one here, not so much - and I don't think they understand what they're doing wrong and the business they're missing out on. I mean, when your customers prefer going to "Monkey-Lube" over you for their oil changes, that's a problem.
My experiences with Lexus Corporate have all been amazing. They replaced the dashboard about 4 years ago as part of a recall, on what was then a 12 year old SUV. I have never heard of a carmaker ever doing anything like that. Over the years I've owned nearly every brand [0], but when it comes time to replace it I want another Lexus.
[0] The Mercedes dealer was great, always getting me a service loaner. They would greet me and knew me by sight - because something went wrong on average every 8.5 weeks with my 1999 ML-320
Nearly all dealerships are run as franchises and there is no "standard" of care beyond some very basic rules. The owner of the dealership(not the manufacturer) will dictate how well the customers are treated and what kind of perks they get. You happened to find a decent Lexus dealership - maybe somewhere else there will be an equally nice Volkswagen dealership.
The thing that does matter is how quickly and easily the manufacturer approves repairs and warranty claims - in my experience Nissan was always dragging their feet, Mercedes was ok-ish, and Volvo was completely outstanding. But even then, it has little to do with "the manufacturer" and everything with their national HQ in whichever country you live in - some operate on tighter budgets so aren't as keen to approve repairs as others. In EU a good solution sometimes is to literally just drive across the border and try to get the repair done in a neighbouring country, if you aren't having luck getting the warranty claim approved.