Re: another closed system with no upgrade path
Hennessy's MIPS project at Stanford (eventually spun out into the company MIPS) and Patterson's RISC project at Berkeley were both funded under DARPA's VLSI grant program, starting around 1980.
Both also took inspiration from IBM's 801 project, which started in 1974, and Tannenbaum's 1978 paper showing most applications used only a small number of the instructions provided by the CISC architectures that dominated in that era.
IBM's 801 evolved into the ROMP CPU (begun '77, running '81, public demo '84), which became the CPU for the PC RT (1986); and the RIOS / POWER architecture (development '82-'89, available 1990). John Cocke was probably the most influential figure in RISC development at IBM, though there were certainly many others, such as Phil Hester.
There was a lot of cross-influence. Tannenbaum's study and others made an argument that was sufficiently compelling to drive parallel development on RISC architectures in a number of places.