You can be as tolerant as you want, that's not how things go for iOS apps. It's certainly not how things go on macOS except when there are no available alternatives.
Windows, Android, and the web, constantly changing so that there's never really been any sense of stability, blind a lot of developers to the fact that good design is both functionality AND looks.
When people complain about designs of controls being out of date, they don't only refer to looks. They refer to how they feel, behave — or more succinctly, don't correspond to the expectations set up by the rest of the system.
To reduce the debate down to looks vs. functionality is reducing things down to the wrong level, missing the forest for the trees, and ignoring the user — a person who often isn't able to express what they need but knows what they want, not often realising that they're the same thing.
