False. If you check Intel ARK, you can see, for example, the i7-2860QM has a max RAM of 32 GB (and this is a processor from 2011). Heck, the i7-8809G supports 64 GB.
JPEG2000 used Arithmetic coding. But, you'd have to re-write the standard and evaluate it to get JPEG to use Arithmetic coding (e.g. does the way JPEG coefficients are read out still make sense with Arithmetic coding)? There are also other algorithms for universal source coding that exist -- theres nothing to say that arithmetic coding is a good choice, esp. given its relatively complex compared to say Asymmetric Numeral Systems (Duda; arXiv:1311.2540 [cs.IT], though I don't remember where it was published) or (Recursive) Interleaved Entropy Coding (Klimesh and Kiely; NASA/JPL IPN Progress Report 42-146).
Arithmetic coding is just the one everyone knows since its taught in information theory 101 (e.g. Cover and Thomas).
There is some level of trust when you read books like this (or really any technical book); for that reason I'd probably pass on it for something by an authority in the field (or their recommendations).
Checkoway et al. wrote a paper "Don’t take LaTeX files from strangers" in Usenix ;login: a few years ago; People forget that LaTeX isn't just a text file -- it is basically a programming language for typesetting.