FTDI Bizarre work around

OK I have two installations of Indigo. One runs under Sierrra on a Mac Pro running 7.0 with zwave, insteon and x-10 The installations sort of works OK The Pro needs a video upgrade to run Mojave. I dont know how long that fix will work with Apple's continoue desire for us to spend money. Machine serves my purpose well even though the OS is no longer supported.
I have another installation on a 2010 Mac Min running High Sierra and Indigo 7..31. I have the FTDI issue although x10 works fine.. and frankly I am not as young as I use to be and I can get the work arounds.to work AlsoThere doesn't seem to be "one" way.... The Mini is not eligiable for Mojave. If I took as second mortgage I probably could replace the hardware. A simplier less elegant solution would seem to downgrade my Mini to Sierra and go back to Indigo 7.0 . With the exception of loss of use of new devices such as Z Wave, and vulnerability can any one point out any thing really bad about this approach??

With the exception of loss of use of new devices such as Z Wave, and vulnerability can any one point out any thing really bad about this approach??

You're also going to lose any plugins that require High Sierra for SSL/TLS. Which will probably be any that use cloud services pretty soon.

I am using less and less cloud services except to my own servers... whoch i need to check because ITHINKi just upgraded their TLS/SSL