That said, your final sentence seems unfair either way. The warning not to roll your own crypto is to avoid the all too common noob pitfalls whereby a reasonably experienced developer invents a security scheme that is completely and utterly broken from its very conception. It's not tell smart people they are too stupid to do crypto (which is a lot of programmers' knee-jerk reaction to being accused of ignorance on any technical topic), it's merely to point out that there's a lot of existing knowledge out there about crypto, and if you don't go learn about it first then your contribution will almost certainly be of negative value.
It's not meant to say don't contribute to OpenSSL or one of its competing libraries, it's meant to say that you need to be grounded in the state of the art and have peer review in order to produce a solid cryptography product.