Anyhow the core team has shown no interest in "handing it over", or release a new PHP 7.2+ version, as the code in GitHub is mostly PHP 7.2 ready already.
Fact is they have deleted several post previously about those things.

Which group of people do you have in mind Daniel?
Haven't seen many beyond the core team or me contributing so fare, even if you and everyone else is free to do so.

Just test PHP 7.3, and if needed provide the needed code change as pull requests, or fork the repo and the whole system: https://github.com/arastta/arastta

Easy peasy ...

It would be nice if a group of people here would take it over and update and repair the issues.
It's a great product if it was looked after properly.

Doesn't look like Denis & Co care for this project anymore, it's looking like it's left to die actually.

But you can test this is you like (at your own risk): https://github.com/syntaxerror/arastta/releases/tag/1.7.0-dev