Nope, not at all. I'm too young to have seen TOS first run, but I watched it all the time growing up in the 70s and early 80s and loved it. I eagerly watched TNG/DS9/VOY/ENT and to varying degrees enjoyed them all, but TOS is still "Star Trek" to me. So I don't really understand this idea that one would have to be introduced to TOS via the sequel series to appreciate it. Honestly, I still rewatch TOS but have little to no desire to revisit the newer shows (and I liked them, I just don't feel the need to revisit them.) The only modern Trek that I have enjoyed as much as TOS is the 2009 movie.
"Canon is only important to certain people because they have to cling to their knowledge of the minutiae. Open your mind! Be a Star Trek fan and open your mind and say, 'Where does Star Trek want to take me now'." - Leonard Nimoy