> But The basic idea is sound. If you invent a novel mechanism and publish it the government will grant you exclusive economic exploitation rights to that mechanism for the next 25 years. After that it is now fair game.

No. it is no way shape and form, good. 25 years is eternity in tech. The impact of the tech is not all that much related to investment either. You are just stifling any competition in the market

> It is an attempt to solve the real problem that it is much harder to be first than second, the guy in first place has to spend all that time and effort to develop the thing, and the guy in second just has to copy the guy in first. To rectify this social injustice the patent system was developed, where the government would grant and enforce economic exploitation rights of the mechanism to the inventor.

It has completely wrong structure for that. First, the duration. Second, the way you can patent vague idea, not actual concrete implementation. It is not used to stop competition from just copying your product, it is stopping anyone in market to compete.