Technology

I can tell you from having looked into becoming an importer of those things maybe a decade ago that the very EU rules for the CE mark (a requirement for them to be allowed to be imported for sale into the EU) cover things like failure rates (max 5% in the first year), minimum hours without failure (10,000 and models must actually be tested on it in order to be certified), loss of brightness with age, minimum CRI and so on.

So yeah, buy them from chinese sellers on Amazon or Aliexpress and you're importing them yourself for personal use in which case no such rules need apply (if doing that I recommend purchasing only from those sellers that mention their product has a CE mark).

In the US, were "consumer right" tend to be this wierd thing that only wimpy eutopean worry about, I suspect there are nowhere the same level of rules (probably the bare minimum for mains wired devices which is pretty much "won't just randomly kill users"), which would mean the stuff carried by the local sellers is China-quality-at-American-prices, so basically the Aliexpress quality but with extra cost to pay the fat bonus of the CEO of the large retail surface.

PS: As a side note to anybody interested in using the CE mark as the minimum standard for their own LED light bulb purchases, look at the packaging: there are very specific rules for the packaging itself, so for example it has to list the brightness (in lumen) with more proeminence than the wattage and also has the energy rating (including a standard design with a graph of horizontal bars) so these things are pretty easy to spot from the packaging of the light bulb.