This may be all about terminology, but acceptable does not mean good.
52 points is not the impossibliilty that you are making out. Is it unlikely? Sure, but that's why it's a challenge. At the start of the season would you have pegged Newcastle to be a CL quality team? When Arsenal were all at sea in the early part of last season, did you think that they would be top of the league 12 months later? They have improved because their fans would not just lie down and accept "oh well, this is the best we can hope for."
45 points wouldn't be seen as progress for me. That's basically just 2 extra wins from a 38 game schedule, after one of the most turbulent and bottom-of-the-barrel seasons we've ever had. I'm NOT lying down and accepting that this is the best we can hope for. I'm effing tired of thinking that mediocrity is acceptable and we shouldn't strive for more. /fvck that. I'm done with being mediocre.