The 2015 DTM champion arguably was the best rookie this year, reaching Q2 on five occasions and scoring Manor’s first point in over two years with P10 at the Austrian Grand Prix.
Having sought an explanation for the snub, the German was told that his attitude with the team during testing in 2015 did not go down so well.
“Some people have an opinion of Pascal and it's just wrong,” Ryan told Autosport.
“The guy is just completely honest, he tries really hard and he's incredibly talented.
“People say he's arrogant. Well I've never seen a hint of that, ever. Everyone who's ever got to interview him comes away saying 'what a lovely lad' and he is.
“If you spend five minutes, or even two minutes, talking to him, you quickly understand that he's a super guy.
“He's not arrogant, he's just completely focused on his job.”
When Nico Rosberg broke the news of his shock retirement in early December, it looked as if Wehrlein, who has tested extensively with the 2017-spec Pirelli tyres for the German manufacturer, just might have had the last laugh in landing the best seat on the grid.
However, Valtteri Bottas now appears to be in pole position to replace the 2016 world champion. Should the Finn join Mercedes, Wehrlein could either move across to Sauber or spend another formative year at Manor where he is held in high regard.
“Pascal is a huge talent, there's no doubt about it,” Ryan added. “He's great racecar driver with great racecraft, great awareness of what's going on around him so we're really, really pleased about him.”