Software development is a huge amount of work and the idea makes up maybe a 1/10 of a percent of the whole work. Every dev has more than enough ideas, what they are lacking is time to develop all of that.

Telling a dev about your great idea is usually similar to going to Mercedes and telling them your great idea, which is that they should make a green Ferrari with six wheels and a cardboard roof.

a) They got enough to do, they don't require additional ideas

b) Ideas from non-devs are usually super high level ("make a Ferrari"), leave out anything that would make them worthwhile but instead include a lot of unfeasible details

Don't take this offensive, it is not meant offensive.

But I have had so many people (mainly those with a business degree) tell me about the great ideas they had on the toilet. Most often with a "if you implement it, you can have 30% of the profit". And of all of these ideas that non-IT people told me, I have yet to hear one that would be worthwhile implementing.