There are many difficulties with Tesla seats.
I noticed that the difficulties are worse for those of us with a moderate to larger build, bone structure. I've been modifying Tesla Model 3 / Y seats for a year and a half now. I've experimented with many designs and finally have a seat that I love and can ride in pain free for many hours drives.
I just purchased my first Model X seat to investigate possibilities.
Turns out all Tesla models share the same base, I believe around the time the Model 3 went into production. The base is metal and is very unforgiving.
All Tesla models use minimal foam and the foam is too soft, lacking protection from the metal.
Sitting in it for a larger framed person, over time will begin to hurt where the hips and thighs contact the "bolsters / wings" because you are actually pressing against the metal frame.
As far as the lumbar and upper seat back.
I found the lumbar support to be troublesome.
In my 2023 Model 3, the lumbar support is made up of three bags filled with air by an air pump.
I found they never adequately deflate. They are difficult to get just right. And for a person with a taller hip bone, the lumbar support is actually doing more harm than good, moving the top of the hip bone forward.
I modified the lumbar support in addition to the seat bottom. I love it now.
If a driver has pre-existing lower back issues, these Tesla seats will aggravate. And the result is sciatica, referred pain, etc.
It can be excruciating to drive for any length of time over a short trip.
I know of numerous ways to limit these issues. And I have a complete rebuild concept to really and truly improve the seats. Because I just started to explore my first Model X seat, I'll have to report back with results. My initial look is that they seat is more similar than different from the Model 3/Y seat and therefore my rebuild should conceptually work in the Model x as well.