Let's make it a felony to have any private contact between companies and legislators then. All communication must be publicly available.
Don't know if it's a felony to violate. But this sounds consistent with the Ethics in Government Act of 1978's reporting requirements [1].
> All communication must be publicly available
This is a bad idea. It privileges those with physical access to lawmakers. It will also crowd out a good amount of honest communication in favor of theatre for public consumption.
That said, there might be a way to thread the needle such that substantial communications around actual legislation get captured. Mark-ups on drafts, suggested language, official policy memos, et cetera.
[1] https://www.opensecrets.org/personal-finances/disclosure
Unless you're younger than 20, you've seen a Congress pass such reforms [1]. If you were around in the late 70s, you may also recall the Ethics in Government Act of '78.
[1] https://en.wikipedia.org/wiki/Bipartisan_Campaign_Reform_Act