The issue is that in real life cricket when someone bowls at 150kph and gets a nick, more often than not the edges DO carry. In fact, id go so far as to say that if you bowl at that pace and someone gets a thick edge the ball is more likely to fly OVER the slips and go for a boundary than fall short. In the game about 80% of the edges do not carry at all (from my own experience of the game) and it makes no sense. From a purely ball physics point of view, the ball certainly cannot lose that much momentum once it hits an edge if travelling at high speed.
To me its logical that if a ball travels at 150kph and loses about 20kph by the time it reaches the batsman, a thin edge will not obstruct the path of the ball in such a way that it will travel to the slips/keeper at a serverely reduced speed.
It seems that the implementation of the edges in the game does not take this into account and still sees the bat as an "obstruction" to the ball and therefore that obstruction will obviously bring the velocity of the ball right down. Rather than doing that it should appreciate the fact that a slender nick will more often than not keep the ball traveling at a decent pace and the ball wont just miraculously go straight to ground. Especially on attacking shots where an edge results in the ball falling to the ground about 5m behind the batsman and thats just stupid and unrealistic - unless the batsman had the edges of his bat glued up or dipped in a pot of sticky sludge.
So to answer your point...it is a big issue, if you are not convinced check some footage of a real game at some point and check how many edges off a fast bowler dont carry. I think you will find that very few dont...perhaps not very few but the majority certainly do carry.
This could possibly be because even fast bowlers on the game are STILL too slow. Shoiab Akhtar in BLC 2005 was genuinely fast and you actually felt hurried...it would be cool if the patch could speed up all bowlers, not according to the kph/mph indication but the actual speed the ball travels at. I cant say that I have ever felt hurried in the game as a batsman...