I don’t work much on UIs as I believe that time is better spent elsewhere and the naked eye is sufficient for 20+ year old windows forms that rarely change.
So I asked Bing :
as an automation engineer can you give me an overview of accessibility testing
- What Is Accessibility Testing?
- Accessibility testing is a software testing method that focuses on making web and mobile applications inclusive for all users.
- It ensures that people with disabilities (such as vision or hearing impairments, physical limitations, or cognitive conditions) can effectively use the application.
- The goal is to conform to accessibility standards and provide an inclusive user experience12.
- Key Components of Accessibility Testing:
- Validation of HTML:
- Start by validating your HTML code. Correct HTML is essential for accessibility.
- Use tools like HTML Validator or the W3C Markup Validation Service to ensure your HTML is error-free.
- Automated Tools:
- Run automated accessibility tools within your browser.
- These tools catch obvious accessibility barriers but won’t find everything.
- Recommended browser plugins include Arc Toolkit, Axe DevTools, and Wave.
- These tools combined can identify up to 50% of common accessibility issues.
- Manual Testing:
- Manual testing involves human evaluation.
- Testers interact with the application, focusing on aspects like keyboard navigation, screen readers, color contrast, and form elements.
- Assistive Technology Testing:
- Use assistive technologies (such as screen readers, magnifiers, or voice recognition software) to verify accessibility.
- Ensure that your application works seamlessly with these tools.
- Integration with Acceptance Tests:
- Incorporate automated accessibility testing into your acceptance tests.
- Run accessibility checks during code commits and release tagging using tools like axe-core or PA11Y.
- Best Practices:
- Follow the correct order: Validate HTML, run automated tools, perform manual testing, and test with assistive technologies.
- Address accessibility issues promptly to avoid breaking changes.
- Collaborate with design systems (e.g., GOV.UK Design System) to resolve any issues related to components or patterns.
Remember, accessibility testing isn’t just about compliance; it’s about creating an inclusive digital environment for all users!
Based on this I investigated the recommended tools Arc Toolkit , Axe DevTools , and Wave
Arc Toolkit ARC Toolkit Overview (youtube.com)
I followed this video and found the tool relatively easy to use, considering
I have at best highly limited experience of html and css.
Then again, the tool was so easy to use I didn’t need much more than that.
Axe DevTools
This tool went further, so perfect for me being a cynic of UI Automated testing. I mean, even a Developer couldn’t go wrong with this, or could they 
fully interactive and not a piece of css or html in site.
But of course, you get what you paid for. Not sure on costs but I would spend a lot more time investigating this, if we moved to modern day web applications.
Wave
Another tool for the cynic in me on UI Automated testing. Very simple and straightforward to use, and no ccs and html in sight
The tool will display any issues and warnings, and guide you to fix these.
All of these tools are useful to meet the minimum requirements, but ethically we should use them to go beyond legal requirements
For a small to medium sized company which attempted the AX route, to adopt accessibility testing for any web applications, then these Tools make a lot of sense over training in Accessbility, HTML and CSS.
As someone who works mostly with data in the backend using SQL and APIs, the Tools would be more attractive than going off to learn more than my basic knowledge of HTML and CSS.
So for me, these Tools would rate very high on the need scale.
The third tool looked the easiest to use and the demonstrator spoke openly about using this as a base tool and advised on some of the limitations. This to me is what we want, honestly and transparency.
With all things, the ethics are a limitation, but this is down to the individual and/or company. These tools will be designed to meet legal requirements as Errors, but we should also always take care of the Warnings and make our sites truly Accessible.