I'll cop to not reading the whole list before commenting, but I skimmed this and didn't really notice anything about speed or performance.

When using tools that can emit 0 to millions of lines of output, performance seems like table-stakes for a professional tool.

I'm happy to see people experiment with the form, but to be fit for purpose I suspect the features a shell or terminal can support should work backwards from benchmarks and human testing to understand how much headroom they have on the kind of hardware they'd like to support and which features fit inside it.