Thank you for pointing this out. I spent so much time with the old ZX Spectrum, but I still totally missed the reference.

For context, Clive Sinclair is most famous for the ZX Spectrum computer https://en.wikipedia.org/wiki/ZX_Spectrum

My very first thought as well, though if it is so, then I wish they should have mentioned that up front. Maybe they don't because of legal reasons? Bleh