His successor is https://languagetransfer.org, which is just a labour of love by a genius polyglot and language teacher.
So much so, in fact, that the owners of the Michel Thomas IP tried to sue him for stealing the methodology. The EFF, back when they actually did anything, shredded them.
https://arstechnica.com/tech-policy/2018/07/no-you-cant-pate...
Please check Language Transfer out and support him how you can.