Reliability
That's not the point.
Reliability is not the entirety of a product.
If you can't load your dishes, the dishwasher is loud, it's not that efficient AND cost more than a competitor, but might last a few years longer, is that really worth that?
Once you go spend 850$ on a Series 300 Bosch you do get the quietness and the efficiency of an Europe style Bosch (it's just a gallon you might save per cycle, but that adds up).
Sure, loading is the same, but it's something most people do accept and can adapt to.
But spending 600$ on a Bosch that fits your needs kinda because it'll last a few years more (maybe) Vs spending the same on a comparable true US style dishwasher that will fit your needs WAY better but might need to be replaced a bit sooner is in my opinion not a cut and dry decision.
Especially if one of the huge advantages - cheap parts - aren't even that true in the US.
I can get a wash pump for any BSH DW over here for less than 90€.
In the US, a wash pump is 200+$ for them aswell.
Now once you go 500 or even 800 series these get unbeatably quiet and you might even get Crystal dry (which adds complexity, but is just amazing) you get to the point where rival products just are hard to come by, and in the US, a Miele of comparable spec is still a lot out price wise.
It's not that they aren't reliable, they just often aren't a great deal in the low end.