Yeah I reckon please look beyond nostalgia. He was pretty mediocre away from home throughout the 1990s and barring 2-3 performances, he didn’t have much to boost for in overseas conditions over his career.
Of course when India will field 2 pacers in their XI, they have to rely on Kumble to be the lead strike bowler. Lack of support is understandable but a career avg of 29 tells us that he had his ups and downs. He is not your biggest match winner by any stretch. That would go to Ashwin.
From Kumble’s era, the biggest match winner was probably Sehwag because he was key to India’s series win in Pakistan and Sri Lanka. Rahul Dravid was key to India’s win overseas
It is more important to watch cricket and assess players than try to slice and dice their numbers and come up with half baked analysis.
In the 90s - Indian cricket's biggest achievement was its home Test record which was built on Kumble being the bowler of difference across both sides nearly every series. Excel fans will discount this saying dustbowl wkts don't count but reality is that if you are outperforming your peers consistently it is a special achievement.
In the 00s - ICT's biggest series wins away
1) vs Aus in 01 at home - Kumble injured and out of series
2) vs Eng 02 , 1-1 draw away - Kumble was top wkt taker across both sides with 14 @36 in a bat dominated series. He had 7 wkts in the headingley win including dismissing both set batters Hussain and Stewart on final day
3) vs Aus away 1-1 draw - Kumble again far and away top bowler across both sides with 24 wkts at 29.5. In the Adelaide test he picked up last 3 wkts for zero runs in first inns 5-fer to keep Aus to 556 when 600+ and triple for Ricky were on cards and in second inns bowled Gichrist when he was threatening counterattack. In Sydney, he took 12/16 Aus wkts on flattest track in years
3) vs Pak in 2004 , 2-1 win. Again Kumble was leading wkt taker across teams in first inns batting dominated series. 15 wkts at 25 while shutting out Pak with second inns 6-fer and 4-fer at Multan and Rawalpindi respectively.
4) vs WI in 2006 , 1-0. Again Kumble leading wkt taker across teams with 23 wkts at 28. The deciding test was again a Kumble second inns shutdown where he took 6fer to bowl WI out defending 269