I've owned to fx boxes, ever.
A Mutron, way the heck back in the 70's stolen by a guitar player; and what was maybe an mxr chorus flange I bought when I started playing fretless and discarded shortly after.
I haven't owned any for years and don't see adding any.
I think your use of 'fx boxes' is key here, and a distinction most people are missing.
Many people here, when they see 'effects' think it means things that radically change your sound -- fuzz boxes, phasers, chorus, etc.
However, many effects are subtle and people don't even realize they are using them.
EQ on your amp? It's an effect. ON/off/volume is all you need, right? What about compression? My first effect aside from EQ was the compressor on my amp. Not all effects are in stompboxes.
Many people have no stompboxes but still use some sort of effect, even if it's subtle or still gives you a clean sound, like adding a preamp. I play in a cover band so most of my stompboxes don't change my sound radically -- a little boost here for heavier parts, a different EQ setting for a different style of music, etc.. It's definitely possible to use stompbox effects and still preserve the 'pure' and 'clean' sound of your bass, though at a different level, or with different EQ, etc.
One of my most important stompboxes is a clean boost that I use if I suddenly discover I'm turned way down (usually at the start of the show, and when we have no sound man and don't run instruments through the PA in many small bars), so that I can bring myself up in the mix while still playing, without having to try to turn up my amp. It sounds kind of silly but it's saved me many times when the drummer and guitar player suddenly decideded to crank it up and I wasn't turned up enough.