Critic when done right will help the people you are giving the critic. It will help them grow, improve or be better.
But when done wrong, it gives meaningless. Worst it will make the other person’s day who being criticised a bad day.
When giving critic, tell why it won’t work from your point of view. And if possible give some input on what you think can be the solution. But with an empathy that the person may take or not what you said.
At the same time we also have to be a good receiving end. Acknowledge their point of view. We are not required to make decision based on the critics. Make decision to use or not to use the advice for the best interest of the project, not us.
Because we and the project are two separate entity.