They do now, yes. The question is not what is the minimum now, but what's the minimum necessary. Every organism alive today is the optimized product of billions of years of evolution; for the author to hold up any one of these as being remotely comparable to the earliest cells is ludicrous.
"They do now, yes. The question is not what is the minimum now, but what's the minimum necessary." - Physicist
A better question would be "What's the minimum observed gene count?", which as you point out, is a very high number because every cellular organism in our entire scientific evidenciary library has DNA.