There's eMMC and SATA, even NVMe via PCI bus (with addons) as well as sd cards (hell even boot from usb now too).

You can also reduce your write wear with putting stuff like temporal logs in ram etc.

I looked into this for an industrial monitoring project. Its possible to configure the SD card as read only but kind of a pain to not be able to change anything.

This is purely dependent on what SD card you are using. If you use a random cheap SanDisk off of amazon it will probably corrupt and fail eventually. A SLC or pSLC industrial card has better ECC, write longevity and power recovery than a commodity card.