As most applications older than a year are called legacy nowadays gcc (~30 YO) or openssl (~20 YO) are not what comes into my mind when asked for "modern" commands.

Neither are for 'dd' or 'tar' (probably 30 YO) from the other comment.

There are probably other, younger commands not following the --long-option pattern, but i think that doesn't make it better to break this convention.