"From many people come [not comes] good ideas." is an excellent sentence in American English, IF the point is that with more people you get better ideas than you do with just a few people. Duo's German sentence and English translation also have this emphasis. The sentence is not just saying that a lot of people come up with good ideas.
I think it is because the preposition aus takes dative and this sometimes results in a “weak noun adding an n ( the n- declension). Certain masculine nouns are weak and take an n ending in all cases except the nominative. Some of these masculine nouns end in e and refer to animals or people eg Junge, Kunde , löwe. The second group are nouns with certain Latin and Greek endings like elefant , astronaut, kommunist.
Das hört sich an als würden sich die Ideen wie Maden aus dem Körper herausfressen.
Aus geht hier mit vielen Sachen: Büchern, Gruppen, Staaten, Köpfen usw. Aber nicht mit Personen. Von Leuten, Lehrern, Männern .........
One could think that good ideas come out of groups made up by many people, but it is too ambiguous to say that that way, and would only make sense in some special cases, not in a general one like the given.
I'm going to guess. I think in English for this idiom you need the simple present tense - come rather than the present continuous tense- are coming. "Are coming "sounds like the good ideas are still on their way and haven't fully arrived yet and it's an event that is occuring at present wheras an idiom is a general statement.