SharePoint List Accessibility Issues

Had a very similar issue with our field teams using iPads. The save button getting cut off is a known problem with the default SharePoint list forms on mobile browsers. What worked for us: we customized the form using Power Apps (yeah I know you mentioned that concern). The trick is to NOT use the default Power Apps form customization from the list settings, because thats what turns everything into custom data fields. Instead, create a standalone canvas app that connects to the SharePoint list as a data source. That way you keep the original column types intact and you get full control over the form layout for tablet screens. Another quick workaround if you dont want to go the Power Apps route - try accessing the list in landscape mode on the iPad. The save button usually becomes reachable that way. Not ideal but it works in a pinch while you set up a better solution.