............. So to extrapolate your question - none of us need even a Cayman - a little 0.9 liter 60hp engine car will happily get us from A to B and reach domestic speed limits.
So buying any Porsche is about wants - your want is as valid as anyone else's but their want is equally valid ..............
This saved me writing an awful lot of words.
My small stable is 'book-ended' in bhp by a 1.2 Peugeot 208 and a 997 Turbo.
For most of my drives in the UK the difference in journey time would be negligible but the 208 would have to work a bit harder. For fun driving, the way more powerful cars perform is key. Keeping within UK speed limits is more fun to do if you can safely accelerate and brake hard and feel safer through corners.