I always used to have this attitude, but I realized a degree or certification "guarantees" you are trained in/knowledgeable in an area to a specific standard. Otherwise your an unknown entity. They don't know you can do it.

There also may be holes in your knowledge, shortcuts or "bad habits" you've learned in your experience which you don't even realise. Sure you can do the job, and 80% of the time you'll do perfectly. Maybe 90%. But there may be things an employer just expects you to know or do, as it's assumed, you have no idea and don't. And then one day it's an issue.

Having that certification says "I am up to a base industry standard to perform this role". And people can work with that. Especially with safety, and also because it's one less thing to be sued about (eg. "they weren't certified? Why the hell were they doing the work then??")

The other possible way, is getting a base role at a company with renown in your field which doesn't require that degree, or is willing to do in job training to get you certified if you need it.

After which you've got that name on your resume. And other companies are more likely to say "oh wow, well XYZ hired them. If they could do this roll for them then they can do this roll for us"
And sometimes you can skip that "must have IT / computer sciences degree" on an IT job listing where the HR won't even look at a resume unless it has that. The correct references can be worth more in some instances.