@kkarhan more people than I thought had ISDN! I’ve only personally known one person who had an ISDN connection and it wasn’t his first. I did know the admin for my local ISP who at one point had four 33.6 modems in some sort of bonded configuration which was pretty rad but obviously not his first modem either.
@sabi local telco offered 20hrs p.m. of ISDN with free channel bonding for ~ €15 p.m. back then...