Sadly in UK they are, even though in practice they can be challenged (since the right to work trumps it, basically). To be honest I don’t think they are much of a factor when it comes to compensation though. It’s largely a cultural issue: SV was largely built by engineers for engineers, so there is an awareness of what a happy engineer can deliver to a company. In Europe anybody technical is just that, a technical resource, a cog. That also links into the degree of freedom they are (not) granted, freedom to choose their tools etc.
I have one, though I work in finance (in London). I’ve heard the same for finance / trading companies elsewhere (e.g. Slovenia). Not sure about pure software companies though...
It’s definitely possible to have non-competes in some cases in germany, but they come with a catch: the employer needs to pay the employee the (usually full) salary for the entire period, potentially reduced by any income from a job. And it needs to be negotiated in the work contract and cannot be unilaterally enforced after the fact.
So generally speaking, they’re only worthwhile for people that have important company secrets.