Yes they did, a few Symbian models used touch, as did original Maemo device that only did wlan initially.
However you have not read the links, not all models were alike.
> The Nokia 7710 is a mobile phone developed by Nokia and announced on 2 November 2004.[1] It was the first Nokia device with a touchscreen
But I think they only released such models with Symbian for a couple of years, before switching to Meego and then later Windows Mobile OS.
The N900 was released more for a question of honour than anything.