I once played a very good game with fake player names in 01-02. At one point I had won the Champions League with Norwich, even though we had never won the EPL. I feel a rant coming on about the "champions" league

Think calm thoughts
Rant aside, I felt that it helped me, as most of the then current squad were still at Norwich when I took over and the fake names enabled me to put aside my opinions about which players are best IRL, which are not always conducive to CM success. So I think that it helps for teams you are familiar with IRL, but for me that doesn't really affect any LLM teams much and most of the poorer players are fairly random from game to game anyway.
My best ever signing was in that game. The only time my scout has ever found me a half-decent 14 year old keeper. He was my starter by age 17 and picked up well over 100 England caps over the next several years before the game gave up the ghost.