Don't dumb down
Confidence and assertiveness, influence and fulfilment arise from being your best self! The person you strive to be every day - learning, growing, improving or enhancing your skills and knowledge, becoming a better version with every new experience you encounter.
So why do some people 'dumb themselves down' then? If we as people, human beings, naturally strive to grow and develop, it doesn't make sense to not show who we are, what we know, what we believe and think, what we want and need. But it does if you want to 'fit in', not rock the boat or bring attention to yourself that might mean you're challenged to 'prove yourself'!
This is where confidence comes in. You know what you know and what you don't (at least when that issue arises, then you can learn). You are confident in what you know... but not always who you are or can be?
You know what you know from your own experience, and no one can take that away from you. You might well not 'know it all' but that's the fun in living life - to learn, to grow, to develop more skills and knowledge, isn't it?
Other people may know more than you and you can learn from them, add to your arsenal of information to meet your needs, develop your options and grow more opportunities! Others may think they know more than you yet have a limited experience or view of the world, of their world alone - and then you can teach them something, or at least help them learn more.
So don't dumb yourself down - allow your self to shine. Share your knowledge, use your skills, help others to learn something new just like you are willing to do, maybe even keen to do! If others shout you down, just be able to stand your ground. You don't have to 'shout' back but you also don't have to pretend to be something you're not when you have more to offer, or to just accept what others tell you - about you, the world (their world).
You have a lot to offer but it may not be what someone else needs right now, or from you. Yet, it is still valuable to other people and to you, so hold onto it until the right time and people to share it with, who will value you and your knowledge, your skills and insights, your understanding and flexible, open and adaptable approach to growth and learning, personal and professional development for more options and opportunities for you - and for them!