I'd say it's more along the lines that everything sells bad nowadays, so western games now appear more successful than before.
Sure, western games are not selling better nowadays...
[PS2] Battlefield 2: Modern Combat (Electronic Arts) {2006.01.26} - 23.747
[360] Battlefield 2: Modern Combat (Electronic Arts) {2006.04.27} - 7.328
[360] Battlefield: Bad Company (Electronic Arts) {2008.06.26} - 27.604
[PS3] Battlefield: Bad Company (Electronic Arts) {2008.08.28} - 41.300
[PS3] Battlefield: Bad Company 2 (Electronic Arts) {2010.03.11} - 67.709
[360] Battlefield: Bad Company 2 (Electronic Arts) {2010.03.11} - 24.539
[PS3] Battlefield 3 (Electronic Arts) {2011.11.02} - 237.160
[360] Battlefield 3 (Electronic Arts) {2011.11.02} - 35.277
[PS3] Battlefield 4 (Electronic Arts) {2013.11.07} - 232.248
[360] Battlefield 4 (Electronic Arts) {2013.11.07} - 9.880
[PS4] Battlefield 4 (Electronic Arts) {2014.02.22} - 107.282
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[PS3] Uncharted: Drake's Fortune (SCE) {2007.12.06} - 55.003
[PS3] Uncharted 2: Among Thieves (SCE) {2009.10.15} - 104.338
[PS3] Uncharted 3: Drake's Deception (SCE) {2011.11.02} - 183.730
[PS3] The Last of Us (SCE) {2013.06.20} - 235.571
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[PS3] Far Cry 2 (Ubisoft) {2008.12.25} - 14.039
[360] Far Cry 2 (Ubisoft) {2008.11.27} - 7.221
[PS3] Far Cry 3 (Ubisoft) {2013.03.07} - 85.114
[360] Far Cry 3 (Ubisoft) {2013.03.07} - 8.285
[PS4] Far Cry 4 (Ubisoft) {2015.01.29} - 54.426
[PS3] Far Cry 4 (Ubisoft) {2015.01.29} - 41.043
Still selling
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Do I need to post GTA numbers now that all versions have sold more than a million in Japan?
Destiny, Call of Duty, The Elder Scrolls... Just to name a few more +200k sellers