This is something I believe has been a serious misconception within the Android and OnePlus communities in the developed world from the start and has really grated me.
OnePlus was never about the US/EU based Android communities and power users. Their launch strategy was to entice those users into buying the OPO so that they could rapidly scale production, distribution, and technical support with a community of people who support themselves and will excitedly put up with stuff like an invite system. The invite system serves as a barrier to entry to make sure mostly technology savvy (early adopter) US/EU users purchase the phones because they will fix it themselves, root it, rom it, whatever.
The real goal was to build that infrastructure and a brand that could then be sold back to their home market and India, where they have an opportunity to enter the market as a realistically priced high-end alternative to iPhones (built for western markets) and the other major Android players. They used Western "power users" to test the device, build some street cred, and then pivot back to the developing countries where it can be priced as a high-end device for the Chinese/Indian middle class that can't afford a Galaxy or iOS device. That's why the OPT doesn't make any sense for US/EU users, we were just a testing platform while the OPT is a coming out party in their home territory.
If you really think about it and break down their moves - the blowup with Cyanogen over India, HydrogenOS, OxygenOS, dual sim and no NFC, etc. their strategy starts to really make sense and we shouldn't expect anymore phones targeted at the early adopter community in western countries from OnePlus.
OnePlus "didn't settle" for the Western markets, they want to go after the next billion users in China and India.