I just did a comparison of the gaps on the 1x bike I'm currently building to the gaps on my 2x Trek. The 1x has a much lower low gear, but the 2x has a higher high gear. The gaps are pretty similar, though a few of the 1x gaps are smaller (unless, of course, I use the front derailleur like I'm supposed to with the 2x).

See for yourself: HTML5 Gear Calculator

But seriously, that link shows a well-designed 2x6 gear system with significantly tighter gaps than a 1x10. I'm starting to suspect that every advance in bicycle gearing technology since 1984 has been motivated by the desire to avoid using the front derailleur.