Knowing how to make an accessible website is so rare that companies pay me money to do it for them. I wish it was good enough for people, much less companies, to rely on.
Even if no attempt at proper accessibility was made, it's still generally far easier to attempt to find an HTML (or other form of UI) element, than to attempt to scroll to the right spot and use visual inspection to find things.
When you're Meta, "generally" might not be good enough. There are just too many bizarre limitations to this, like image buttons, or interactivity attached to random elements (making a div a link, etc)
