I think you mean ”companies like Trimble and Autodesk”.
”You could sell the same software at low prices to both "classes" of customers”
Slightly disagree. How do you brand the product then? ”Design your next hobby woodworking project” and ”Design next award winning apartment complex” are promises that speak to totally different markets.
So I would argue it would not make sense if you care about the brand.
Thats why these open source alternatives are so great - they are actually targeting a market no-one is interested to serve commercially and can have hobbyist specific brand without having to voice cringy boasts about being a perfect clone of something for the users of the said clone.
Expansion of software patterns to adjacent underserved markets via open source is really nice.
The point here is, the actually largest share of consumers doesn't get served by the "market".
It's a systemic failure and people fail to grasp the exemplary nature of it.