Intel made a processor with a GC in hardware once
When Sun brought out their SPARC hardware the language they run was ported to that, and ran about four times faster clock-for-clock.
You can gain some measure of the Rekursiv's success from the fact that the only complete machine known to still exist can be found on the bottom of the Forth and Clyde Canal, somewhere around the Possil Road Aqueduct.
The founders parents fled from Austria during Nazi times. In Austria we speak German. The English word "recursive" is "rekursiv" in German.
Fascinating guy.
(This whole thing also reminds me of the Intel 432... had some similar properties)
and david bacon (et al) - https://files.catbox.moe/bipg79.pdf