I would personally say no. Like Sean already mentioned while Football Manager is one of the most interesting games to play.. its because it creates and shapes a world you as a manager live in; you get a connection to the team, players (either already existing in real life or not) and even tactic (there have been tactics on here that I still remember like Bossa Nova in FM13.. amazing)..
When someone else plays it is their world.. and for me it become much more apparent that it is not real.. For some reason all the people that have been playing or streaming FM on youtube/twitch have decided to play the matches in 2D.. which makes me even less immersed in what is happening.
I have tried watching people play the game.. but a person just clicking through menu's.. buying players you have 0 connection with because its not players in your world etc, then using a terrible standard tactic (for example I have seen one person who just.. plays 4-5-1 in every game he plays.. does not matter if its Barcelona, Liverpool, Norwich City or Doncaster)..
Twitch therefore is even more difficult than youtube because on Twitch you cant edit anything, you have to talk about and during everything (even when you are just on the squad screen).. and it feels like you are listening to a dragged out football talkshow.. Youtube content however, as far as I have seen it, works with some strange formula where you get to see match highlights.. a team update and then 1 match in full (lame 2D) commentary.. On the one hand this is better because it feels much more like a team update that you are following... but the less you see and less you are involved also has an influence (for me atleast) on what you do see. For example when people are showing their transfers.. they just show them as a list of names.. going over profiles.. saying that player x is going to be great.. but the fact that you did not find or choose it yourself.. or that it is a great newgen in your own world for example.. turns it just in a list of names .. then when those names go into a match its a list of names that play football..
Therefore I think that FIFA is watchable because it is almost like you are watching a normal game, while you also watch for someone his/her skill and commentary.. In FM, if you dont really spend hours upon hours on building your tactic.. there is not really that much skill involved.. commentary whise.. do you really want every second/minute/hour of FM with commentary? And during a match do you really want to watch 2D dots (that already include commentary) where someone talks like a supporter on every missed shot? "Ohhhhhhh Messi so close lad".. It might be for others.. but I would pick to play FM over watching it every day of the week.. and you are probably playing it so much that you do not want to watch even more of this great game