For the second part which is the sportsbook, I won't tell a lie, they are better in this aspect. They can still have about 75% winning in their top sports bettings, which include, football, boxing and basketball. These aspects of gambling are easy to predict by anyone who is conversant with them too, so I see no big deal here. Except if there is no money involved, I can still compare their analysis with mine. This will be for filtering. That is the highest I can do because I can't ever be independent of anyone in my sports betting this way, it will only degrade me.
I agree with your opinion, sportsbook gambling can rely on predictions from sports analysis gambling experts, their predictions are not disappointing for win ratios above %70 and the loss ratio can be said to be less unless we don't get lucky, usually gambling experts master certain sportsbooks, especially in football matches and big fighters in certain gambling games. However, I also agree that don't rely on gambling experts in gambling on slot gambling, lotteries and other types of lucky gambling, but you can consider several things from gambling expert advice when it comes to sportsbook gambling because sports gambling can be analyzed to potentially choose the winner.