Legal exposure for inaccessible sites keeps widening globally, but the stronger argument is commercial: accessible sites reach more customers, convert better on mobile, and share almost every property that search and answer engines reward. WCAG 2.2 AA is the sane target.
Accessibility still gets filed under compliance, which undersells it badly. The disciplines that make a site work with a screen reader, real heading structure, labelled controls, sufficient contrast, keyboard operability, are the same ones that make it parseable by the machines deciding who gets cited.
They are also just good mobile design. Bigger tap targets and readable contrast convert sighted thumbs on sunlit phone screens too.
Where to start without a consultant
Run Lighthouse's accessibility audit, fix the mechanical findings, then do the two tests tools cannot: navigate your enquiry flow with only a keyboard, and read your homepage with a screen reader. Twenty minutes will humble most sites.
Bake the standard into new work rather than retrofitting old. Accessible-by-default costs almost nothing at build time and a fortune afterwards.