Modded Atari 2600 runs at 22,000 times the processing power of the origina

You can't just take the quotient of the processor clock frequencies and multiply by the number of threads! A current generation processor does a lot more in a single clock cycle than they did 30 years ago. Pipelines etc... didn't exist back then. The 6502 only had a single 8-bit general purpose register (although the index registers could also be used when not accessing memory).

An Intel Core i7 is probably more than a million times faster.