Have some confidence and don’t assume that other bigger companies are smarter than you are, think about what you can improve. Most of what Google have to offer, they bought from smaller companies that had the confidence to do just this.
When you have that, it probably doesn’t make much difference if you add some extra friction to your sign up flows or your UI is a bit janky.
When you’re the new guy who no one has heard of: that’s when you need design. You need to catch people’s attention, win their trust, and make it as easy as possible for them to get to the aha moment, because any minor inconvenience can be an excuse to close the tab of yet another random app and move on.
All that to say, startups often lean heavily on design to stand out from the crowd, so if I’m looking for good design and UX to emulate, I look for startups that are still small but gaining in popularity, whether bootstrapped or seed/series A. That’s typically where you find the best practices being implemented to a high bar. Once they get too successful, complacency and other priorities start to kick in and they are no longer the best examples to follow.
As a UX designer/researcher who focuses on exploring novel interfaces, if every company rethought their UI from scratch that would be great for my job security. But realistically there are good reasons why most companies default to following established UI conventions:
First, your users generally have significantly more experience using products from big companies than yours, and differences are often perceved as problems. See Jakob's law.
Second, sometimes a company that releases a novel solution does fantastically well. But more often than not it ends up being a lesson in why the convention existed in the first place. See Chesterton's fence.
Third, unless you want to make the UI a differentiating factor for your product then any time you spend iterating on novel interfaces is time you could have been spending on your company's core competencies. See... I dunno, Seth Godin, basically any startup blogger?
A strong but unspoken rule when anyone gives you advice is (and I feel like not everyone knows this anymore so this bears repeating): use your critical thinking skills to decide if the advice is applicable and appropriate for your situation.
I learned this after many attempts early in my career to copy what the MS conferences were talking about.
The thing is that what a big company do can be good (in fact MS was fine back then!) but are problems for big companies, and have issues that you don't need to copy, worse: copy without knowing. For example, microservices, horizontal scalability, massive telemetry to cover all, etc are problems yo don't want to get.
What it works much better, is to copy a small/medium player that is very well regarded. Like for example, think in panic, vlc, etc. Small/medium players that have good reputation need make more effort than big players, and are on top of the good things by necessity.