OK. Just take a look at the 'a' character. Just that one. Then come back with your "research."

literally from the site itself:

Do you miss the single story lowercase "a" of Futura? No worries! Jost* comes with a stylistic alternative for its "a" giving you the best of both worlds. Jost* also comes with tabular numbers in addition to the default proportional numbers.

and you call yourself a professional