tbh the pi4 is still solid for an under-$100 solution, just stick it on an external nvme + usb3 cradle and crank the swap to 2-4 gb so it isn’t swapping on sdcard (always dies first).

if you want “less hobby-ing around”, grab a used optiplex/thinkcenter tiny i5 on ebay (you’ll nab 4-core/8-thread, 16 g ram, nvme slot) for ~120-150 usd, slap ubuntu server on it, and you’re done,case the size of a paperback and way quieter than a full tower.

either way isolate the utxo db and blocks on bare nvme; spinning rust just drags forever.