Heart burn is a digestion tract issue, lying down only exacerbates the symptoms.

Even if that was the case, just lying like 10-20 degree off completely flat completely negates the issue.

tbf, almost every single chair out there is wildly un-ergonomic. Whoever came up with all that 90 degree “perfect posture” bullshit must be exhumed, revived and then executed again. Just get yourself a laptop and work from bed if you can, otherwise, get a recliner that can go back at least 45°, find your comfortable angle, then plan the rest of the setup around that.