Sure, if you plan to clean every 25k (or whatever) I wouldn't bother with a catch can, but that's a tiny minority. Walnut shell cleaning (the best method) isn't cheap - and all that time before 25k you are losing power and contaminating your oil.
Valve guide wear is typically more common on engines with 100+k miles, not sure how you determined bad valve guides were "the main culprit" but that is *not* true of most well cared for engines - maybe your Audi engine was junk (wouldn't surprise me). That engine, like the M cars, runs high boost, which = more blowby
https://us.autologic.com/news/cleani...ection-engines