Axar Patel : Playing his 4th test match and already took 32 wickets with 5 fifers.
Kyle Jamieson : 9th match and touched 50 wickets, fastest NZ bowler to take 50 wickets.
Axar Patel played all of his matches in the minefields of sub-continent, which supports spin bowling. His 4 test matches were played in - Chennai, Ahmedabad (x2) and Kanpur. I am not denying the fact that Jamieson also played most of his matches in SENA region, but he has played against tough opposition all the time. He is yet to play any test matches against weaker teams like Sri Lanka or Bangladesh. Don't know.. but I would be rather cautious before claiming that Axar is a better bowler. Let's see how he performs outside India.
Let's go by modern standard. In modern times quickest bowler to reach 50 wickets is Vernon Philander (7 match). He also took all wickets at SENA condition, 1 opponent was Sri Lanka. Speaking of spin friendly wicket, you might want to check legendary spinner Shane Warne record in India particular. You might lose respect for him after checking his numbers.
I can go on this list for like 1 full page but i hope you got the point. If we're following this logic then Don Bradman is also average batter because he never batted in Subcontinent and virtually never faced a quality spinner in spin friendly wickets.
Coming back to your tough opposition and minefield argument. Seems biased opinion to me because for some weird reason SENA countries fast friendly pitches are considered good and spin friendly wickets in subcontinent are considered bad.
BTW Kyle Jamison only played at NZ and England only (including 2 match each against Pakistan and WI, ended up with 26 wickets in 4 games). This is his first game in India.
Axar Patel played against only England at home (3 tests) and NZ is the second team.
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