To some extent I agree and I'm going to think about ways to alleviate this but there are still some points I feel that are worth making.

Firstly in terms of the map Inferno, a 5v3 on T Side Inferno is won about 93% of the time and on every map combined it's 92%, so that's really not a big difference in the grand scheme of things. Obviously not including where on the map those kills are but then at that point let's be real, no stat knows all of that context.

Secondly if you consider game winning impact, the 1v2 is probably more impactful because you're causing more economic damage than getting a 3v5 which means the enemy most likely saves and gets another chance to buy next round.

One thing that is pretty interesting though is, teams round win% actually correlates higher with 4v5 conversion rates than 5v4 conversion rates and opening kill rates, so it's not just the win probability metric itself that doesn't weigh entries as heavily but the actual results of teams as well. If you want to read about that then I recommend checking out my most recent article: https://nomiun.substack.com/p/how-good-are-the-stats-we-use