I agree with all of these points, and let no one think I'm defending the game with my statement. To be fair though, they are starting to make changes towards making hybrids viable with legendary abilities. A perfect example being BM for Warrior, if you upgrade Fierce Strike in the BM tree it'll do it's regular damage but then increase your crit chance with non-bm abilities by 5% for 20s which if my memory serves me well crit is incredibly useful for Paragon. Another good example is if you upgrade Seasoned Strike in Warchanter it deals damage but then increases all damage and healing of non-Warchanter abilities by a scaling amount.
Now, do I think these are the way to go for hybrids? No, I'm still a firm believer that if I'm not totally unaware of how talent trees work I should be able to make some fun and interesting builds with just my talent points and not play around with secondary systems like the masteries or legendary abilities. However I do like to try to give credit when it's due.