I think people have a bit of a popular misconception about the Explorer advertising thing. What's happening is that MS is adding a banner to Explorer advertising paid OneDrive subscriptions.

I totally agree that it's massively inappropriate, but I do think that most people are imagining third-party advertising which is not what's happening - a lot of people might not consider the current situation to be an "ad" necessarily since it is pushing a subscription for OneDrive, a Microsoft product that you already have installed. It's more of an in-app purchase kind of offer.

They don't necessarily make it easy to turn off all the weird ad-type-stuff, but they don't make it impossible either. A quick tour through settings on install can get rid of it all.

There is still one absolutely heinous crime though - your system comes preinstalled with Minecraft and Candy Crush (and a couple other bullshit softares), and if you uninstall them, Windows 10 will automatically reinstall them. You have to do esoteric shit in the registry editor to disable this. It infuriates me.

I recently did a fresh install of creators update on my laptop. Not only does it have crapware bundled that I had to uninstall, it has placeholders for apps from store which is literally advertisement. I also got edge ads when I was downloading other browser. I preemptively disabled all other "suggestions", but saying that windows 10 doesn't have ads is a blatant lie.

It's all in the settings. I never had ads or privacy problems, but if you leave everything at the default settings, you'll have those problems

I formatted a few weeks ago. After installing Chrome and opening it, a popover appeared over the Edge icon in my toolbar explaining how much faster it is. I've also seen a few OneDrive ads.

I have also not seen any anytime. It is also true that I only use managed Enterprise, and a pro at home where I have o365 subscription.