You've gotten plenty of good data above, here's an anecdote that is close to your situation:

I bought a Domane 2017 SL6 disc after 20 years of riding an old Schwinn 7 speed hybrid and then a Trek 520 touring bike - I'm not a racer, mostly long recreational rides and touring. When I added the 520 many years ago, I said "Yup, leaning over more is faster" an average speed increase riding with the same routes with the same tires and bikes that weighed about the same.

With the Domane, the riding position is a bit more upright than the 520, a bit more leaned over than the old hybrid. The bike is lighter and I'm lighter - my deal with myself was to lose 20 lbs and then buy a "mid-life crisis" bike. But I had a number of rides on the old bikes at the lower weight. On the same 32mm Schwalbe tires, I'm another 1-2 mph faster on my typically rolling hill/1 or 2 decent climb 30 - 50 mile rides. On shorter flatter rides, not as much difference, maybe .5 mph but that is kind of in the margin of error.

I don't use a power meter on the outdoor bikes (I donated the hybrid to a cycling advocacy group and the 520 is now mostly used on an indoor trainer on Zwift) but since I've been using Strava for a while, the "Matched Ride" feature shows that my faster times on all common routes are on the Domane and where I came close, it was usually on the 520 at a higher average exertion level.

Bottom line - if you feel like buying a new bike, you can use the "I will get to work faster..." as one of the justifications...