I don't think people generally understand horsepower, even a lot of people who think they know about cars and maybe think they know the basic math and equations.
It's a bit simplistic, but if your engine puts out a reasonably constant amount of torque over different RPMs, then horsepower is proportional to RPM. If you have 100 peak HP, and a similar figure for torque it implies you have that horsepower at over 5000 rpm. So if you are accelerating moderately and your engine is turning maybe 2000 rpm, then it's only making 40% of the peak power, which in this case is 40 hp.
Say you had 300 hp, but you don't rev to 5K - you'd be aware of how it feels and think 100 hp is nothing - but you are getting barely more than that at 2K.
I actually have a newish car with 300 hp and an old one with about 150, and so from experience, the difference in power is very misleading, because the low powered car is usually running at twice the RPM on the highway, whereas the high powered one has an automatic transmission that really doesn't like to downshift. So it doesn't feel especially powerful unless you force it to rev.
Now and then I read an article about a car from roughly the late 70s, early 80s, when it appeared most cars made a ridiculously low amount of power. People say "wow, that big V-8 only made 200 hp" (or something like that). But comparing it with the torque figure should make it clear that if you compare it to a modern engine at a given, low RPM it's going to be much closer. They simply didn't produce torque and power at high RPMs. People like to talk about engines with low end torque, but in my opinion, there's no such thing - only engines that don't have high end torque.