I've heard this take a lot over the years. It's shortsighted and lazy IMO.
When 2 teams are as equally matched as those 2 were, when one gets extra chances they don't deserve, eventually they will capitalize. Think USSR over USA in the 1972 Olympics. How many chances were the Soviets given to score on the final play? You could say that team USA also had more than enough chances to win in hindsight. But as things played out, they shouldn't have had to play that final possession and should have won regardless of other things they didn't do right.
If that Samaki Walker half court shot wasn't counted in GM4, the Kings would have been up 3 games to 1 and may have never had to play a game 7. Things surely would have played out differently with the Kings up 3-1, but suppose for a moment they were almost the same except that you give the Lakers the calls that went against them in Game 5 and the calls that went against the Kings in Game 6 --- the Kings win in 6. And nobody's talking about FT's or airballs.
The Lakers really only have Game 5 as an argument when the Kings have both Game 4 and Game 6. Much larger mountain to climb and overcome.