Here is an accurate assessment from Hoops Hype on Lebron James (written in Jan of this year)
http://hoopshype.com/2016/01/12/these-five-stars-are-quietly-leaving-their-primes/
James is still one of the best players in the NBA, and he’s averaging 25.8 points, 7.4 rebounds and 6.0 assists per game – not far removed from his career averages or even some of his best seasons. By the end of the year he’ll be deservedly in the Top 5 in MVP voting and will take his place on either the first or second team All-NBA.
It may not be obvious by his stats, but the first indications of his aging are starting to show in some of the more advanced numbers… even if his overall production and effectiveness has yet to decrease noticeably.
The league average around the basket is around 55 percent every season, and LeBron James has continually been by far the best finisher in the NBA consistently over the past years, only matched in individual years by players who exclusive dunk the ball such as
DeAndre Jordan and
Tyson Chandler. In 2013-14, his last season in Miami, LeBron finished a preposterous 504 of his 673 field goal attempts, a 74.9 percent rate, at the basket. This season, James is down to 64.9 percent, which is still elite, but down from his crazy historic levels.
More interestingly, the first signs of LeBron’s decline are better shown by the fact that he has been blocked nearly twice as often within ten feet of the basket, compared to previous seasons. Up from around 5 percent of James’ attempts being blocked, closer to 9 percent in 2015-16.