When I think of modular, I can't help thinking of canon and their camera lenses.
Many years ago, when film was king, and you had motorised cameras, you could hot swap lenses from one maker to a different make body, by using an adapter.
Canon decided when updating their bodies, to change the lens mount. Meaning all their own old lenses and people who had favourite lenses from a different make, could no longer use the bodies.
So even Canon purists had to buy new lenses.
They refused to make an adapter for any lenses except their new lenses, with the new style mount.
So everyone who had built up a collection of bits were screwed!
My friend/tutor, had to either spend a fortune building a new kit, or buy the new Nikon body which didn't need an adapter, and even accepted his canon lenses (with adapter).
So with that in mind, I don't like modular stuff, cos they only got to change a screw/mount whatever, and you're collection is worthless.