Note: It's entirely possible to build a site that scores a 100 on Lighthouse, but be an abject failure in Accessibility compliance. We've done it ourselves on my team inadvertently (combo-box failure), so never forget that actual, manual testing with screen readers is 100% necessary. Automation often works against you when it comes to achieving compliance.

To wit, you can create a really, really inaccessible site that scores 100 on Lighthouse: https://www.matuzo.at/blog/building-the-most-inaccessible-si...