They both have SanDisk 2 GB cards in them. I vaguely remember naively thinking along the lines of "less space => less bit density => better reliability".
It mounts a ramdisk on /var and only occasionally copies the logs from ramdisk to SD card. That way I can still see all the logging without hammering the SD card quite some badly.
I basically mounted all logging and webpages on tmpfs, and the DB resides on the SD card being written to every 5 minutes.
Just understand that anything that is written to tmpfs will be lost if you have a reboot. It might make troubleshooting difficult if you need to preserve them for whatever reason.
It has seen many installs over the years but it's now a backup DNS server. Looking at the filesystem this one has been a PiHole since 2018, it has essentially ran 24/7 bar some reboots and me moving between places.
I don't write anything to the SD, it all goes to RAM at /dev/shm and the PiHole will simply have to redownload the lists the few times it goes down. It would download them anyway daily.
Exact same kodi-setup and sandisk cards, and has been happily running for years without problems. Disable all logs, media on smb/nfs, and off you go.