I admit this is nitpicky, that language is naturally evolving and corporations cannot make rules about how English should be spoken but "Legos" isn't strictly correct. The correct term, per The LEGO Group should be "LEGO bricks". At one point they had this written on their website:

"Please always refer to our products as “LEGO bricks or toys” and not “LEGOS.” By doing so, you will be helping to protect and preserve a brand of which we are very proud, and that stands for quality the world over"

Also, though "Legos" is somewhat common in North America, it's less common in the rest of the English-speaking world.

British English speaker here - Lego was always a collective noun for me, like sheep. You might have a piece of lego, and some lego, but never 'a lego' or some legos.

It was oddly jarring to come across Americans on the internet, who had a totally different take on this!

(yes I realise you can have "a sheep", my example isn't quite right! Perhaps it's more like sand or rice)

Lego's argument always struck me as absurd. Imagine Ford doing the same thing: "Please refer to our vehicles as 'Ford vehicles' or 'cars', and not 'Fords'. By doing so..."

I think the temptation to start a car company that markets "Ford" cars is probably less than the temptation to put on your box of bricks that they are compatible with Lego bricks.

If the company doesn't take reasonable actions to protect the mark, they lose control of it.

What does that have to do with how people call actual LEGO bricks?

I figured https://news.ycombinator.com/item?id=22276586 made the context clear enough.

Ford doesn't worry about losing their brand. Lego does. So Ford regularly uses the brand as a noun itself, Lego Group asks people to not do that.

The only risk I can see is becoming a generic term for "construction bricks". I don't see how me calling my genuine Lego bricks Legos contribute to that.

It's how trademark law is written, use as a noun indicates it is becoming a generic term.

>I admit this is nitpicky, that language is naturally evolving and corporations cannot make rules about how English should be spoken

You said it yourself.

Unfortunately, there's a lot of slop in lego gears and axle holes, and quite a gap between blocks when affixed that don't line up when sliding together.

I've used Lego stuff on the job for prototypes and experiments as well. They're overall really good and handy, but some simple mechanical tasks can get really messy or rattly.