[anonymous_sorry]

Those things got invented anyway though, without being patented. The right question, in my opinion, is whether there are important software innovations that would have been significantly delayed, or kept secret, or never discovered at all, if software patents weren't a thing.

And if so, do they outweigh legal costs and chilling effects of patent trolling, and the inefficiencies of people having to engineer around patented ideas.

Intellectual property is a fairly artificial concept. It's quite "big government" when you think about it - government grants a monopoly on the application of an idea. It is only worth preserving if it makes the country richer.