I ordered a couple of things on Temu last year just to see what it was like. A kitchen storage thing and a USB cable. The cable arrived after 5 weeks, and the storage thing took even longer. Quality? The cable kind of held up but it was really lightweight plastic, not reassuring at all. The storage thing broke after two weeks of normal use. So yeah, technically you get what you ordered, but don't expect it to last.
What nobody really talks about is there's a real problem with customs fees in France. Plenty of people ordering think what they pay is all there is, but if your package goes over a certain value you can end up with a surprise bill from the delivery person. It's rare that it happens but it does, and it's a trap that's not marked anywhere.
If you really need something specific and you can't find anything better elsewhere, yeah it might be worth it for 5€. But you have to accept that you're gonna wait ages and the thing might not last very long. It's not really reliable for stuff you need quickly or that's supposed to last.