Actually, all modern living organisms are equally evolved. That applies from microbes to whales. There's a difference between modern microbes and modern whales. Yet, they all are equally evolved.
I get that terms like "more" or "less" evolved don't make sense given that everything alive today has evolved for the same amount of time since LUCA. But selective pressures will drive more and less change during that time to different morphologies in different niches.
Plus, some features of animals have emerged much later in the history of life than others. Like, amphibians have been around a lot longer than birds have. Even within species, like humans, there are goups that contain older features and groups that contain more recent ones.
So how do we talk about those differences when terms like more and less don't work because everything is equally evolved?