There are industry-standard benchmarks that measure TPS. See for example (or maybe not even for example; it may be effectively the only one in town) http://www.tpc.org/information/benchmarks.asp.
And of course, anybody considering buying such a machine will spend quite a bit on evaluating how it performs under their load, just like SPEC (https://www.spec.org/) says something, but not all.
I've looked at the tpc.org maybe 13 years ago. It never made sense to me to use it as a measurement unit back then and it still don't make sense to me now. :)
