Vint Cerf has called the decision of it being 32 bits as silly and arbitrary, like having a car odometer with 40 digits. If he had pushed for more, he thought nobody would have taken him seriously.

The idea of 32 becoming scarce was laughable.

Also the complaint about ipv6 isn't a technical one, it's a usability one. Extending it to 48 bits would have been easy enough for people - like international calling.

Those 16 bits could be in hex, as a convention, so something like "(4EA7) 8.8.4.2".

However, I've constantly heard that the 128 bit hexadecimal with colons just looks too complicated and inconvenient.

You might be brilliant and find it easy but to a lot of people ipv6 addresses look like cryptographic hashes