This might just be a misunderstanding. I believe Loon is still owned by Google X, which changed its name to X Development and sometimes just calls itself X. Then of course you have the unrelated Musk company also called X.
Not a misunderstanding, mostly rumors [1]. When Loon shut down [2], they made a non-assertion pledge for roughly 200 patents originated during the project's lifetime [3]. Part of the platform was an LTE stack [4], and those patents aren't in the non-assertion pledge. The interesting bit is:
> To support ongoing innovation in the High Altitude Platform Station (HAPS) communications industry, Loon transferred a number of stratospheric ballooning and networking patents to partners working in similar fields.
Hard to say for certain of course without any public records with regards to an IP transaction or patent/FCC filings showing the transfer of patent assignees. Google and Fidelity invested $1B in SpaceX previously (2015), which leads us to the thesis that Loon died because of Starlink.
I think believing random comments off of hacker news without verification or source makes questionable sense. The name "X" isn't unique (which is part of the problem with it) as you're exactly discovering.
