It is very possible. My commute used to be 23 miles, the end portion in Sacramento. My typical time was 55 minutes, but under 50 minutes was common and I did it in under 45 minutes more than once.

Traffic lights in urban centers are typically timed for 25-30 mph, which incentives speed. Add in the fact that we get to draft the traffic, and the urban portion can be done with good speed.

There's lots of fast riders out there who don't ride professionally or even race.