Scenario:

const columns = [
  {
    name: 'Column',
    width: '36%',
    mobileOptions: {
      fullWidth: true,
    },
  },
  // ...
];

This outputs the following HTML:

<td class="euiTableRowCell euiTableRowCell--isMobileFullWidth" style="width: 36%;">

But unfortunately, .euiTableRowCell--isMobileFullWidth doesn't override the inline styles, so fullWidth: true is not working on mobile.

Possible solutions

1. Add !important to .euiTableRowCell--isMobileFullWidth so that it overrides inline style widths
2. Add the width property to mobileOptions, so users can do this instead of using fullWidth:

const columns = [
  {
    name: 'Column',
    width: '36%',
    mobileOptions: {
      width: '100%',
    },
  },
];

No strong preference/feelings here on which folks go with - whatever's either easier or feels better API-wise is fine by me!