Pretty much an opposite to the question made in this post. Now, many people on this sub are enthusiasts so this question may sound like a little bit crazy to ask on here. However, you may have a spouse, parent, friend, or some other person you know that isn’t really that big of a car person and may feel differently. Maybe mom is terrified to get behind the wheel of your 707 hp Challenger Hellcat, for example. Even among some enthusiasts or petro heads, I find some of them will set limits. I know some people will get behind the wheel of a 305 hp Civic Type R, but feel the current American Muscle/Pony cars are too powerful for their platforms to effectively use that power (as opposed to something like a mid-engine supercar).
Most cars aren’t driven hard at all. You can usually get away from a pack of stopped traffic in a Camry with screaming CVT because most drivers are finishing their texts before driving.
You need 300 or so hp because when people are being stupid and you need to get away, mr 50mph blocking the left lane will wake up and floor it as soon as traffic clears, so your easy 50-70 pass is now a stupid 70-90 roll on. You want a bit more than the average for easy placement in a pack and to avoid clumps-this isn’t a slow car fast thing.
Beyond 400 hp, you don’t gain much. I find cars like this frustrating, as there are only so many highway on ramps.