I'm not sure you understood me.
> Pretty wild to see HN users say that startups should not be allowed to compete with incumbents.
Pretty wild to be so misinterpreted. Of course startups should be able to use a patent. The point is just that an entity that does not make use of it also does not get to make use of the exclusivity granted.
A "startup" that only exists to enforce patents would be the definition of a patent troll afaik, hence me liking the idea that one needs to use the patent to make use of its rights. (Edit, Wikipedia: "Patent trolls often do not manufacture products or supply services based upon the patents in question.")
> how could MegaCompetitor block further use without a lawsuit (which could result in an injunction)?
Who said anything about "without a lawsuit"? See the part where I said that patents should perhaps only:
>> be enforceable by those that produce the invention
So when MegaCompetitor makes wipers from the example above, they can enforce that EvilCorp doesn't make wipers during the patent's validity period. Since the government has a monopoly on force, that means they need a lawsuit with an injunction as goal. (I'm not a lawyer though, nor natively English, hope I'm understanding and using the word injunction correctly.)