We're way off in the weeds here, of course, but that's cool. I don't mind playing in the weeds.

What you've done there is analogous to Dear Leader's argument "it's Constitutional because it is not a tax and is a tax". You've tried to say "it can write the single value 00000001, which is eight values". Either that's one value or eight, pick one.

The definition of a Turing machine has requires very few capabilities. One of the very few things required by the definition of a Turing machine is that is has to be able to update memory one value at a time (block writes aren't good enough). That's the DEFINITION of a Turing machine - it's a machine that writes individual symbols to a strip of tape of other storage.

You've defined a language that can only update eight bits at a time, and additionally you've said it updates them only in certain patterns. That's not Turing complete.

If we want it to be Turing complete, we can interpret it as one value by saying that the LANGUAGE writes "1" and the HARD DRIVE happens to store that physically with eight molecules. The language would then be Turing complete since it's updating the single value "1". Fine. The language can write 1010101, 11111, 0000, 01010, or any other series since it's writing one value at a time. Perhaps the hard drive stores "10" physically as 1111111100000000, but the hard drive is going to read back what was written to it. Write a "1", get a "1" back. That's part of the definition of Turing complete because the storage in a turing complete system can be like a dumb piece of paper - it doesn't change what you write to it. Given that the tape doesn't change what's written to it, the language can write valid machine code and get valid machine code back.

You can't have it both ways. If "1" is one value, it can write "1", then write "0", in whatever pattern is needed to produce valid machine code. If it can only write the eight separate values 0,0,0,0,0,0,0,1 that's not a Turing machine.