Beat me to it
Most industry insiders, including some I know personally who are very highly regarded, all agree with the nature of SkyTrax. The kindest thing I heard said is "Dubious"
Seemingly it's more related to the spend an airline has. The metrics they use are opaque so who would really know.
Favoured more by marketing types to brag about things like "5 star airline" and so on, and looks good, but realities are it's not exactly accurate. I mean people just need to use their noggin and wonder how carriers like IB get so high up, or AC seemingly rated as "best for families" and so on. Doesn't really pass the pub test.
Having written all that, I mean the top few winners are no shock and I think most people who have any experience with any or all of them would tend to agree that the likes of QR, SQ, NH etc would all rate very highly for onboard product and service, younger aircraft and overall leading design hard products (think QSuite, or SQ A380 new Suites) blow most others away - along with lounge offerings and so on.
So the usual top 3-5 are probably fairly universally agreed upon.. some others.. not so much and some listings see a head scratch.