In my experience, removable SD wouldn’t hold up to an application like this.
If it were held in and held against some robust contact pins it likely would be fine, even under automotive conditions. There are SIM card slots that are used on heavy vehicle computers and controllers (the ones that run the engine and so on) that are robust enough to hold a SIM card in place for years of excessive daily vibration.
I suspect that designing reliable spring contacts isn't as easy as it seems...
The trade-offs for a high vibration environment are very different.
You are not wrong that a soldered eMMC (compared to a eMMC held by a ZIF or a removable SD Card) would be more mechanically stable and potentially faster (A fast uhs-ii sd card compared to a cheap slower eMMC for example), just saying that Tesla already use removable SD cards in production cars today (which doesn't brick your media unit if it dies or dislodges).
Storing the OS on a removable SD Card is (imo) a bad idea, but if they are really interested in these logs they already have a easier to replace removable storage "drive" they could write the logs to instead of burning up the eMMC.