I would argue the exact opposite. Web standards have steadily increased in quality. The web has become much less quirky over the years and you no longer need to emulate broken browsers in order to get a functional browsing experience.
Building a web browser is hard, but it's not impossible. Just look at how much progress Ladybird has made in a year. If Ladybird isn't an existence proof I don't know what would qualify.
Our industry as a whole is way too willing to put up with broken software for literal decades because building a better version is believed to be impossible. And that's how we end up squandering endless (volunteer) resources to marginally improve old projects that essentially have no future.
We can have a better future, but only if we choose to build it. As Henry Ford said: "Whether you think you can, or you think you can't – you're right."