The increase in attribute scores (5 X the base roll on 3D6) makes the resolution of many situations easier. You might have lots of good reasons to like earlier editions. I'm not a fanboy making an argument that 7th edition is objectively better.

And I like 7th edition, which I do see as an improvement, not just churn for its own sake. I started running a COC campaign soon after Chaosium released 7th edition, so I have a fair amount of experience with it. I've played Call of Cthulhu since the 1st edition (In a box! With illustrations by Gene Day!). I was running Horror on the Orient Express for d20 Call of Cthulhu without much trouble at all, for instance. At this point, it's more useful to consider a game or a module for the non-game-mechanic ideas and suggestions it provides, rather than the raw crunch, because it's not that hard to convert across. Heck, I had a cobbled together set of rules I was using with FUDGE for convention games, because making a character with 25 percentile skills can be a pain in the ass when other details can be more important. And then beyond that there's plenty of Lovecraftian rpgs that aren't based on percentiles: d20 CoC, Trail of Cthulhu, Cthulhu Hack, Realms of Cthulhu (savage worlds) and Silent Legions. There's CoC7e, there's Delta Green, there's whatever Cubicle 7 is going to spin up, there's Raiders of R'lhyeh (ha! I can't spell) and of course the competition provided by the previous editions of Call of Cthulhu, of which there have been a lot of printings. There seems to be a fragmenting across the Cthulhu D100 space.

Call of cthulhu 7th edition