It is.
Lack of sleep and leisure time will do more damage in the long run than the short term benefits of 16+ hours of learning a day will ever do good.
I’m fine with the dongle because all I ever use the headphone jack for is for listening in my car (no bluetooth), so the dongle just stays on the end of the aux cord in my car.
No dongle would obviously be better, but it’s a very minor inconvenience for me,
And the two established businesses just artificially lower their prices to keep out the competition, forcing the third to stop trying to compete.
https://www.youtube.com/watch?v=35PUIhDUFZo
Very relevant.
Basically, it’s a combination of new foods and exposure to new bacteria.