Nothing whatsoever to suggest the bug has always been there. Almost everyone I've spoken to has only experienced the increased losses in tourneys since Chapter 15 was made available.
Well i dont know the answer either, but i hope you're wrong.
I have been getting the feeling tournaments are too hard for a while now. (especially scrolls and magic dust and even some crystal)
and i havent noticed a difference in difficulty in the last tournaments at all compared to the 9 weeks ago, and i do enough tournament to think i should have noticed. So im hoping you are wrong and the overall difficulty will go down once the bug is fixed.
If this bug was always there, it would make sense with my feeling that tournaments are too hard even if you level your wonders high. At the moment it feels like levelling combat wonders isnt worth it at all
as example my personal score 9 weeks ago vs score now, and i should mention i have been doing slightly less in tournaments lately since i didnt see the point to do more (competitionwise)
planks 9660 vs 8760
crystal 8580 vs 8322
scrolls 7134 vs 9000