>The only specific thing Ubuntu did for beginners is sending CDs for free

Assuming you are not malicious I will kindly help with your bad memory, Ubuntu had always very good proprietary driver support, this made laptops actually work and helped beginners. I also remember they had a graphical installer compared to Debian and for sure this was beginners friendly. Maybe some other distro offered easy way to install and come with proprietary drivers setup but I can't remember a deb based distro doing that.

Anyway you were wrong, the CDs were not the only thing made Ubuntu appeal for beginners, there were Linux magazines with CDs each month and they were not super expensive , my first linux was a Kubuntu 6.10 from a magazine and I am still running Kubuntu today though i ran Debian, Sidux, Arch, Mandriva, SUSE in the past when I had time to try different distros, compile custom kernels etc.