You may wonder what's wrong with them? Afterall, satem dialects show us clearly a distinction between *ḱ and *k. Of course, we should have no issue towards this contrast at all. However the problem lies with how certain we are that *ḱ is phonetically realized as a palatalized consonant in IE. The nitty gritty of it is that we only assume that *ḱ is palatal since this is how it ends up in satem dialects where we find the palatal affricate *ć in its place. So it's long been believed that since IE *eḱwos becomes Early Indo-Iranian *ećwos then it follows that IE itself had palatal consonants. Oh dear, what a careless leap of logic! The evidence from satem dialects merely shows conclusively that early Post-IE dialects had palatal consonants. Centum dialects lacked palatalization altogether. But how can we explain IE without palatalized sounds?
To explain IE without palatalized stops we need to first explain what we plan to do to fix IE. This is how we should update IE's sound inventory for the 21st century:
Why that's blasphemy! Delicious, isn't it? Now get ready. Here comes the reasoning behind it.
- Palatalized stops are to be reinterpreted as plain stops:
*ḱ, *ǵ, *ǵʰ -> *k, *g, *gʰ
- Plain stops are to be reinterpreted as uvular stops:
*k, *g, *gʰ -> *q, *ɢ, *ɢʰ
We know that pronouns and numerals contain the so-called palatalized stops exclusively and yet this is completely counter to the principle of phonological markedness. We expect simpler sounds to be used for such common words and yet clearly IE is a theoretical maverick: *eǵoh2 'I', *ḱo- 'this', *sweḱs 'six', *déḱm 'ten'. This in itself is clear proof that these sounds must be interpreted as plain, not marked with added palatalization.
There is also the consideration that the sequences *ke or *ek are rarely reconstructed for IE. By acknowledging that traditionally transcribed *k is in fact marked and pronounced further back in the mouth, and further by pairing it with *h₂, we realize that the reason for the lack of these sequences is because *q, *ɢ and *ɢʰ colour vowels just like *h₂ does. So whenever we see *ka or *ak reconstructed, we should remember that they are in fact *qe and *eq (e.g. *kap- 'to seize' is to be understood as *qep-). I will go out on a limb and bet that the few words that are reconstructed with these sequences of *ke or *ek are falsely reconstructed, either because they are based on false evidence, because the proof points rather to its "palatal" counterpart, or because the vowel in question should be long (n.b. that long vowels resist colouring normally caused by neighbouring *h₂).
When we start pondering the effects of this reinterpretation, we begin to see a different story concerning the development of satem dialects unfold. We then realize that the Satem dialect area was the innovator, pushing the two stops *k and *q frontward in the mouth. Hence briefly, dialectal *ḱ and *k spread across a portion of the IE-speaking area where the rest of the dialects kept original *k and *q. This regional isogloss was now the seed for satem dialects like Indo-Iranian and Balto-Slavic. However, palatal velar stops are unstable and quickly turn to affricates, so it wouldn't have been long before *ć and *k were heard throughout Satem IE as became the norm in later Indo-Iranian.