I've seen this debate come up quite a few times, and I think there's more to it than simply saying that designing sounds from scratch makes you more creative.
A preset is just a starting point. You can spend hours tweaking oscillators, filters and modulation to create a patch from scratch, only to find it doesn't work in the track. Meanwhile, a factory preset might be exactly what you need, especially once you start tweaking, layering or processing it.
That said, preset browsing can easily become a habit in itself, where you spend more time searching for the perfect sound than actually making music.
I think there's a difference between knowing how to design a sound and knowing which sound a track needs. Both are valuable skills, but they're not necessarily the same thing.
What's your take on this? Do you prefer starting from an init patch, or do presets help you find ideas you'd never have come up with otherwise? And is the real issue with presets themselves, or how we use them?