Yeah idk it seems to vary. I have 2 controllers and one has an ok (not great but fine) dpad, while the other constantly presses directions that I don't want to press, and it's been like that since I got it.
There actually is a silent and very subtle revision they made to the dpad less than a year after Switch launched (iirc around the time of the Xenoblade 2 controller). The protrusion out the middle of the underside was made slightly longer, which makes you less able to push down all four directions at the same time. The chance of undesired diagonals is very high either way but just slightly lower for the newer one.
Even the improved version is one of Nintendo's worst dpads ever (including handhelds) imo, with only the GameCube's coming remotely close. A huge step back from Wii U Pro's dpad.
Eh, YMMV. My first pro controller lasted from release until about 4 months ago. Second one is used from a friend who also had it since about a year after release and no flaws. Among my entire circle of friends we only had one person with any issues at all, and that was someone who got one of the very first batch ones with the wonky D-Pad. Sent it in, got a replacement, all good.
Might be based on region though, dunno whether the EU stock is different from say, the US.