And if you did want to write it in close to one line, it wouldn't be particularly difficult either.

Simply outlaw _selling_ (or giving away) of ad space in public.

You want to put your own logo on your storefront, side of vehicle, brochure, public bus, charging station? Sure. You want to sell that space to the highest bidder to place their own ad? Nope.

This would eliminate 99% of billboards, bus stop ads, etc without creating any ambiguity as to whether a business is allowed to identify itself in public.

One caveat might be that it would be desirable to carve out an allowance for e.g. "10% of sales go to Charity X".

The length of a law doesn’t reduce its murkiness - in fact it makes it more pronounced. That is why (in the common law systems) there is so much discussing and re-discussing of topics that plenty of other cases already covered, using new approach angles. If you make laws longer and more complex, you only make them serve more those that have the budget to explore all branches of the decision tree.