The open standards don't protect from the "Big Techs". See AWS and the open-source technologies that they use. "Tech monopolies" is the too broad category to create working solutions. Some monopolies use the network effect, like Facebook, Twitter, Uber, etc. They are protected not by closed technology but by the community. Building an app like Uber is much easier than making a company like Uber. The same applies to smaller companies/services like Reddit or even HackerNews.