Most modern ThinkPads only have soldered RAM/max out at 32GB so were basically a no-go for me. They also had 2mo+ delivery lead times for BTO options, which also put it out of the running. I wasn't super happy w/ my last Thinkpad (X250) and general sentiment seems to be that they've continued to go downhill, so unless they release something that hits it out of the park from a design perspective then I'm not so interested. (The Z13 is actually pretty neat now that it's available and discounted, but only 2 USB-C ports doesn't work for me.)
Dell QC has been pretty terrible the past decade, and they're inferior in basically every way (Intel-only, mediocre cooling solutions, meh battery size, expensive, long-standing (like multi-year, basically entire product life cycle) unresolved bugs/incompatibilities even for their dev edition versions, soldered RAM, awful support, etc).
One other thing is that if you are a Linux user, I really don't see much point in rolling the dice/fighting obscure compatibility bugs (most of them being BIOS/ACPI bugs that are hard to impossible for mere mortal end-users to fix) when there are similar (or better) alternatives that are known to work OOTB, or better yet, explicitly support Linux.
Obviously most office workers or casual users don't need that much memory, but I've hit swap before w/ 32GB of RAM just with browser tabs and electron apps, so I bet lots of people with 8GB or 16GB hit swap and get slowdowns and just assume their computers are too slow, when really, more memory would have solved their problems. Also, I'm also sitting at 36GB of wired memory usage right now with a single VM running. Anyone running containers or doing any virtualization will want as much memory as they can get, as would anyone working with any number of data sets - I've hit swap on 64GB working w/ "simple" sqlite databases and doing basic pandas work. I also do video and photo processing (including a lot of large panoramas) for fun on the road and that's another whole class of workloads where more memory is better. As mentioned by others, large compiles also benefit from more memory.
Anywhere, here's the rub. I bought my 64GB memory kit for $250. It cost an extra $125 at retail to add an extra 32GB of memory, which almost all laptop manufacturers have decided not to even allow as an option for segmentation/planned obsolescence purposes. Which is fine, that's their prerogative, but since there are enough decent options that allow more memory, it also means that I, or anyone else who needs more RAM just won't be giving them any money instead.
Dell QC has been pretty terrible the past decade, and they're inferior in basically every way (Intel-only, mediocre cooling solutions, meh battery size, expensive, long-standing (like multi-year, basically entire product life cycle) unresolved bugs/incompatibilities even for their dev edition versions, soldered RAM, awful support, etc).
One other thing is that if you are a Linux user, I really don't see much point in rolling the dice/fighting obscure compatibility bugs (most of them being BIOS/ACPI bugs that are hard to impossible for mere mortal end-users to fix) when there are similar (or better) alternatives that are known to work OOTB, or better yet, explicitly support Linux.