Making mathematics accessible to the general public isn't part of mathematicians' jobs, nor is it something most of them care about.
If you want to write some articles that make mathematics more accessible to the general public, and you want to use longer variable names in order to do that, nobody is going to stop you. It's unreasonable, however, to expect mathematicians to try to do this at the same time they're doing their actual jobs.
There is job security in keeping it arcane. Lawyers know that, too. But, since some professional mathematicians teach and others need to communicate with business people, you'd figure there might be some interest.
If you want to write some articles that make mathematics more accessible to the general public, and you want to use longer variable names in order to do that, nobody is going to stop you. It's unreasonable, however, to expect mathematicians to try to do this at the same time they're doing their actual jobs.