TI with the TMS9900 was in a similar position as IBM with the 386: both threatened their micro/minicomputer markets. This is why TI didn't release other TI-99-like machines. TI also expressed disdain towards hobbyists.
Edit: It might be cool to make a higher-spec TMS9900 home brew system.
Edit: It might be cool to make a higher-spec TMS9900 home brew system.