But the price of cellular data has come way down. For instance when the iPad was first introduced, it was only available in the US on AT&T and was $25 for 2Gb of data per month. Now I'm paying an extra $20 a month on T-mobile for unlimited data for my iPad.
The cellular iPad wasn't even worth it for me until I could get unlimited data for $20. For that amount the extra convenience of not having to tether and basically having a second phone is worth it since you can get and receive regular phone calls to your paired cell number from an iPad even if your phone is dead.
I pay a total of $180 a month for 5 phone lines unlimited data on each + an iPad, unlimited 512Kbps tethering on each + 10Gb of high speed tethering on one for my son who uses his cell phone for his only internet. This is with T-mobile. They also throw in a family Netflix plan (4 simultaneous streams) with it.
Heh, ironically, the "wired" internet is surely 10X or more faster than a decade ago. Anecdotally, I have a 1 Gbps connection now; year or two ago I had a 250 Mbps connection, and 2-3 years prior to that it was 50Mbps. Ten years ago it was, what, 5Mbps or 2Mbps.