I think it's not about 'just'. It's more about how unsolicited is the advice. How strongly the person in trouble is looking for a solution.
I had a few times the experience that when I had a programming problem it was immensely helpful to tell about it other person, even non-programmer, because it forced me to state what the problem is so clearly that in theory this person should be able to understand. This made me notice some things about the problem I didn't notice before which sometimes enabled me to either find a solution or slightly, acceptably alter the problem so its solution is way easier.
And even if after explaining my problem I'm still stuck, then the advice the person who listened to it gives me, while not being the solution, will activate my mind even further, because trying to explain why this solution won't work can point me out in the direction of how this solution or the problem itself could be developed or adjusted so that it could possibly work. This thinking might reveal to me completely different solution.
So by all means, please say to me "why don't you just ..." when I'm asking. I probably won't do what you say, but it might lead me somewhere and I really do appreciate listening to me and your input as it might be the key factor that will enable me to find solution.
I had a few times the experience that when I had a programming problem it was immensely helpful to tell about it other person, even non-programmer, because it forced me to state what the problem is so clearly that in theory this person should be able to understand. This made me notice some things about the problem I didn't notice before which sometimes enabled me to either find a solution or slightly, acceptably alter the problem so its solution is way easier.
And even if after explaining my problem I'm still stuck, then the advice the person who listened to it gives me, while not being the solution, will activate my mind even further, because trying to explain why this solution won't work can point me out in the direction of how this solution or the problem itself could be developed or adjusted so that it could possibly work. This thinking might reveal to me completely different solution.
So by all means, please say to me "why don't you just ..." when I'm asking. I probably won't do what you say, but it might lead me somewhere and I really do appreciate listening to me and your input as it might be the key factor that will enable me to find solution.