Plenty of victims of human sacrifice were buried with a plethora of artefacts. Conversely, many of the world's most powerful lie in very unremarkable graves.
Prehistorical "history" is more a reflection of what we think than what happened thousands of years ago.
Yes, there is some variation in opinion in how the findings can be interpreted but most of the differences between 1916 and now would be due to that now we are MASSIVELY more rigorous in our approach to such findings.
The smug is strong here, and it's unfounded.
Maybe they've like, already thought about this possibility, before making the determinations that they did? Like it's not just the presence of "stuff" but the kinds of stuff (and a whole range of other factors) which distinguish a high-prestige burial from a sacrificial burial.
Being as, you know, they've thinking about these things for years and years, and you haven't.
Jumping to conclusions about the competence of others (based on a snarky observation or two) isn't very helpful, either.