I haven’t tried a USB stick but as they and SD Cards tend to use NAND flash with various approaches for read/write but in theory shouldn’t really be that much different. My torture/test Pi on my desk is a Pi4 with a M.2 adapter to provide a SanDisk 64GB SSD as the main drive, so this is very achievable and very affordable as eBay has many smaller M.2 SSD’s at a reasonable price.
This isn’t really a RAK question, but for what it’s worth, I’ve quite a few Pi’s being very well exercised, three with RAK boards on top and none have killed the SD Card. The oldest Pi is the intranet server and is a v1, so the card is pretty ancient. I fly High Altitude Balloons that have multiple logs, write temp files for the transmitted images and save a sequence of low & hi-res files constantly. We usually have them run for a few days to soak test a new rig. I only use SanDisk or Samsung cards, class 6 or above.
You can mitigate the read/writes by moving the log files to RAM disk and have them write to flash at reboot or periodically. Depending on how big your Pi memory is, you can do the same with the database files. As it’s on a network, the other option is to setup a network share on something else and have the database files on there - not brilliant for overall system efficiency but as there shouldn’t be a huge amount of database work, this is an OK solution too.
There are numerous entries on the internet about alternative ways to boot a Pi, but they do have complications depending on which Pi and how you ask it to boot - to the extent you need to be careful you don’t permanently turn a Pi in to a USB only device. This is less of a problem with a Pi4 due to the boot rom style. The official details here:
These will explain how to move ANY Pi image to the storage of your choice.