So, there are two answers here, which are fairly different.

The first is that in many ways, the Soviets deserve their reputation. Simply saying "Everyone did crimes in WW2" is a kind of ridiculous act of hand-waving that ignores context and magnitude, among other factors. To say, for instance, that American treatment of POWs was the same as Soviet treatment of POWs would be patently absurd, as the latter was a complete and utter abrogation moral norms, while the former was generally in total accordance with with expectations of the Geneva Convention, and that difference isn't changed by the fact that there are well known exceptions, such as the killings by guards alleged to have been carried out at Dachau. I've written about war crimes committed by the Soviets in several cases, including rapes in Germany, and their ill-treatment of Poles in the period of World War II. I've also written about American behavior, talking extensively about looting here, but as I note at the end, however poorly it may make us think of the American GIs, it really doesn't place them in the same category of criminality that routinely was carried out by Soviet soldiers, in the same way that the poor treatment of POWs and the conquered populations by the Soviets doesn't some how lessen or excuse the same crimes, often in greater orders of magnitude in turn, by Nazi Germany.

But, in many ways the Soviets don't deserve their reputation, especially in terms of how their military capabilities are remembered. The simple fact is that until very recently the historiography of the Eastern Front was quite skewed in a negative way towards the Soviets strategic and tactical capabilities due to over-reliance on German perspectives in the Western retelling, and this even continues today in more popular history style accounts. I've written extensively about this previously, although also make sure not to miss /u/kochevnik81's response in the thread too.