And until there is a consensus that the risk of SEC enforcement against broker-dealers has diminished, there won't be much additional competition (and what competition exists will bake the cost associated with the risk into the equation).
In practice, I've never come across company filing a Form 10 to register previously issued restricted shares.
That said, I'm relatively sure that there would still be difficulties clearing sub-penny stocks (there will be regulatory review), but you could at least avoid the attorney fees associated with legend removal (I'd expect costs of around $1k to clear/sell given sub-penny fees, vs. the $3+ that I'm currently looking at for that plus legend removal).
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