This proposed law is not about OSS philosophies. It's about the use of public tax payer funds to provide excessive profits to an industry that is controlled by a monopoly. I don't have anything against software companies making profits, but under rules that provide fair competition, and today these rules do not exist. I applaud any effort in government that will balance the competitive playing field, including legislating OSS software for government use.
It's also about security. Relying on a single provider for a closed source application does not allow either public or internal audit of the actual functionality of the code.
We need rules that promote fair competition and security. Rules that don't lock the government in to a single source provider (for services, upgrades, maintenance or product). I see OSS type rules as the only valid solution.
We all pay an enormous cost because of the state of the software industry. It needs reform.