They used to be. From what I can tell from personal experience they have fixed a lot of their QC problems. I suspect they had a push to capture market share by simply being cheapest with disregard for quality in the late 2000s/early 2010s. The build quality in their laptops from back then were atrocious. Nowadays it seems to be on par with other manufacturers.

Not in my experience. I have two Acer Notebooks. They don't get much use now simply because they are a bit underpowered for a lot of current software but they have been working flawlessly for years.

Chrome OS team i.e. Google does the bring up + testing on these not Acer.

Not a good endorsement. Google sells very shitty hardware and on top of it their customer support sucks.