Your reply is a pointless cop-out. I'm not talking about one species versus another, or the totality of changes. I'm talking about specific, undisputed, relatively disadvantageous mutations, that never-the-less get passed-on and cascade through populations. A fact which invalidates your previous assertion about "based on fitness/utility" being a "fact".
To continue this conversation you really, really need to give at least one example of this "fact" you claim exists, otherwise it cannot be usefully discussed.
I notice the appearance of the word "relatively" now linked to "disadvantageous mutations". What do you mean by that?
Notice that the citation of "sickle cell anemia" above (and other cases of genetic diseases due to having two copies of a gene that confers advantage when present only once) do not support your claim at all. They are advantageous on average, and thus spread until an equilibrium is achieved (if such an equilibrium exists). Similarly harmful genes that only show up after reproduction ceases can spread through random drift since there is no selection mechanism removing them.