If you do get sued, if you immediately remediate your website, you may be able to get the lawsuit dismissed on mootness (there’s no longer anything in dispute, i.e. plaintiffs are arguing your website is inaccessible but you’ve already made it accessible). This definitely does not mean you should wait to fix your website but it does mean you may have an out.
The ADA itself holds different organizations to more/less stringent standards based on a host of factors, government funding being a major one. Government agencies themselves are usually held to the most severe standards. That said, while ADA has adopted WCAG as the defacto standard, from what I’ve seen it appears they’re going with AA compliance as the most reliable one. That said, we’ve done work with some organizations who’ve chosen to comply with AAA in an effort to be as buttoned up as possible from an accessibility and experiential perspective. We’ve also worked with some who have tighter budgers and aim for level A compliance and have a more “react and repair” mindset when they discover anything in their site that is giving someone hardship from an accessibilirt standpoint.
The question of ADA’s exact wording comes down to two issues: 1) whether the ADA applies to a website at all, and 2) if ADA applies only to websites that have a physical connection to goods and services available at a physical store or location, or if it applies to all websites even if they don’t have physical spaces. Courts are split on these issues but one thing is for certain: the tide is moving toward ADA compliance for websites, and the lack of specific legal wording prohibiting web discrimination has not stopped businesses from being sued.