It is not possible to infect 8-bit computers from the 1970s and early 1980s with malware. The operating system is on a dedicated chip that would have to be physically replaced with a new chip that contains the crippled OS. This is in stark contrast to more modern computers where the OS can be modified by software (e.g. malware).
Is the question about infecting the 8-bit computers connected via the ESP32-based FujiNet device, or about infecting the FujiNet device itself?
As Cherryhomes himself points out, that device is VASTLY more capable than the vintage hardware/software to which it's connecting. A compromised FujiNet running in a trusted network would be a significant security issue.
