I priced out BCS and Grillo units when I first moved here and in the end ended up getting a subcompact hydrostatic tractor and it frankly has probably worked out better for me (6.5 acre property ... 1/2 acre vineyard/orchard, 1/2 acre garlic + market garden veggies).

It's likely because the importation of the BCS units into Canada just ends up making them and the attachments quite expensive. If I was in Europe, or even the US, I think they'd be more cost effective.

The tractor + loader ended up being a more useful overall implement because the loader is just invaluable on a rural property generally. So many things made easier by being able to move around heavy loads. And snow clearance with a 70" snowblower is an entirely different story than walking behind a 30" one. I used to have Gravely walk behind with a snowblower on it and my back suffered for it.

I have 3ph rototiller, snowblower, rotary mower, posthole auger, toolbar with discs, s-tines, wood chipper, and single bottom plow. And access to a bunch of other stuff from the neighbours. All of those things would be potentially cheaper for a BCS unit, but much harder to get, and less powerful. The used market for standard 3ph attachments is much easier to deal with rather than the niche walk-behind stuff.

On the lower end I use a wheel hoe. And I'm currently working on restoring and electrifying an old planet jr unit.

The BCS and Grillo units are really neat. But the small farm market isn't big enough for them here to get proper dealer support, used equipment supply, and deal with the importation issues. All of the neat attachments weren't available to me without dealing with Earth Tools in the US, with all the brokerage and customs and shippings issues that would come with that.

I'd largely agree, there's a reason 3PH(and SSQA) are ubiquitous. If you support that standard it opens up a massive market of compatible attachments.