There needs to be a larger gradient of funding options than "Waste cash until unicorn" or "rent-seek until next bailout", and "dominate small-to-medium market niche" or "sponsor and penetrate next manufacturing commodity".

We've seen so much wastage from the prevailing financial model in SV tech.

I don't understand. Your options are (1) be small, try to grow fast, (2) be big, (3) be small, don't try to grow fast, and I'm not sure what (4) means. What else is there?

What behavior would prevent a technology like ultra-cheap phased arrays from being locked up due to the corporation seeing some potential in either the technology or the team to buy them, but then not giving both the leeway to develop the market for the technology further?

In this specific case I guess we don't know the full picture of what Lattice Semiconductor intends to do, but there are many examples in software of startups getting acquihired and then the team dissolving into new projects that are more familiar or closely aligned with the pre-existing business model of the company.

Since it's always possible to just turn the startup into a subsidiary I'm sometimes confused as to why this happens, unless if it's an issue of maybe brand dilution or the market opportunity being too small to be worth the overhead of keeping a separate entity tied to a larger one. Which is a part of why more opportunities for low-growth or long-tail companies would be important, since now in the case where the means for bringing the IP to the market are eliminated no one gets anything at all.

Use-it-or-lose-it provisions for all acquired technology, by entities over a certain size?

If you are demonstrably developing a piece of technology, kudos. It's yours, you bought its owner.

If you are not doing anything with it, you're required to offer FRAND license terms to anyone interested in the technology.

Would at least make the tech available that's currently getting tossed in a corporate closet in the basement.

I can't believe this is getting downvoted. It's the equivalent of sticking your head in the sand and hoping that if you can't see a bad thing then that bad thing doesn't exist. This is a clear case of incentive design and too strong of an arm in preventing acquisitions can come back to bite you. Don't pretend this isn't the case, acknowledge it and factor it into your beliefs around optimal anti-trust law.

That there exists a strictness of anti-trust law / prosection which is harmful does not opine on whether or not stricter anti-trust law would be harmful or beneficial.

So a bit of a red herring.