[baz00]

I think the thing is that no one in the industry gives much of a crap if it's open source or not. Most of the EDA users out there are on Windows so there is no reason to ship source for that platform either. The end users only care about the price which is why LTspice is popular.

Also worth noting that the SPICE engines have been modified heavily over the years in the open source side of things. Inside they look nothing like the original open source SPICE distributions.

When I'm, rarely, doing EDA work it's LTspice for simulation, KiCad for capture+PCBs and Excel for any calculation glue. All are chosen for price/performance rather than open idealism. One just happens to be open source.