The two lessons that you learnt are truth and nothing but the truth, and there is hardly anyone that will reasonably dispute your lessons.

I have this to say;
You are lucky to have learnt this lessons before making some mistakes, many newbies always make the mistakes before they learnt their lessons and that is still the faith of many people in this community. Being able to learn your lessons from other people's mistake is a great privilege for you not to be victim of what other people suffered.

So far we must learn to deal with the exchanges because they are very much part and parcel of the cryptocurrency industry, many of the newcomers that locate the crypto industry came through exchanges as the means of getting and storing coins and they will continue doing what they know even if it's wrong till a new knowledge is giving them.