The PinePhone will be launching soon, and you could install any flavor of mobile Linux you want if you are still interested in owning a smart phone: https://www.pine64.org/pinephone/
My escape plan is to use the dumbest feature phone I can find and also carry a pocket computer (running standard Linux) that lacks cell capability.
I'd love to get a Cosmo but I'd hate to carry it around everywhere due to its bulkiness. I guess that might be your concern as well.