It seems that in 2016 there was a ruling[1] that said it's not illegal to sell them _with_ an OS preinstalled (and included in the price).

> The CJEU ruled that it's legal to bundle PCs with software without indicating their prices separately, and that offering consumers no choice but to buy the PC with the software is also legal, "unless such a practice is contrary to the requirements of professional diligence and materially distorts or is likely to materially distort the economic behavior of the average consumer with regard to the product, a matter which is for the national court to determine by taking account of the specific circumstances of the case in the main proceedings."

[1] https://www.pcworld.com/article/3117584/consumers-have-no-ri...

I’m pretty sure it’s Microsoft that pressures manufacturers to not offer PCs without operating systems not “Europe”.

I don’t think they ever went as far as threatening companies for selling Linux systems but it’s well documented that they withdrew discounts from suppliers offering OS/2 with computers.

Microsoft did that after the US government made them stop charging for a Windows license after every computer a vendor shipped... regardless of the OS installed.

IBM just included a copy of FreeDOS for every PC before it sold it's business to Lenovo.

This was over a decade ago.

Yeah, and Lenovo gets around this by shipping every machine at least with FreeDOS, which technically is an operating system.