Most shoes are not great insulators - they insulate but how knows who much. electricians sometimes buy special shows that do insulate. Those shoes come with care instructions and dust on the outside compromises their insulation.
The care instructions and dust you mention sounds likely to be super important when you're casually touching live stuff while standing on a grounded floor.
In an electrostatic situation, the electrons can flow (almost) freely without the shoes / tyres and so a large differential between body / ground will not build up. With shoes, you'll need a large difference to build up (10kV? 20kV? More?) before it discharges.
Anyway, there is clearly a difference between these situations - even if the shoes don't provide magical protection. But the shoes are not magical, as you correctly describe.