> Being closed for free doesn't mean it isn't open source for those that pay.
True, but...
> This was a common model before FOSS took off and it is still quite common in enterprise products.
No, it wasn't and it's not. “Shared source” for paying customers was common before Free/Open Source Software (FOSS) took off (“Free” doesn't modify “Open Source”, they are essentially synonyms that identify the same license features but which are preferred by different ideological factions that prefer those features for different reasons.) Shared source does include access to the source, and it may include some rights to create derivatives (usually with no or restricted distribution rights), but it is not open source.
Modify the runtime library source code or use it as it is. You get the assembly language and Pascal source code to the System, Dos, Crt, Printer and Turbo3 units. It comes with a batch file to help with recompiling and building TURBO.TPL."
It's no religion; the terms have well-established meanings.
> What matters is having access to the code, whatever form it might be.
The legal permissions you have to make use of the code very much matter, too. And those vary considerably among non-Open Source, source available/shared source license arrangements.
True, but...
> This was a common model before FOSS took off and it is still quite common in enterprise products.
No, it wasn't and it's not. “Shared source” for paying customers was common before Free/Open Source Software (FOSS) took off (“Free” doesn't modify “Open Source”, they are essentially synonyms that identify the same license features but which are preferred by different ideological factions that prefer those features for different reasons.) Shared source does include access to the source, and it may include some rights to create derivatives (usually with no or restricted distribution rights), but it is not open source.