No, it is significantly more difficult in other EU countries, yes.
Here in Finland for example the process is actually no different than for a non-EU migrant (same amount of time taken for an unproblematic application, same amount of appointments). You are just much more likely to be accepted but in fact they do still reserve the right to reject people. And it is, probably unintentionally, much harder to exist in Finland as a non-resident as you can't have a bank account, can't use foreign phone numbers for most things and any phone you can get is very limited (can't call many numbers, etc). I couldn't even log into the local eBay for the first 6 months. All the Nordics I would guess are similar.
And people have contested in the comments to you that Spain is not actually so easy as you suggested...
I actually don't know any western country that is as easy to move to as the UK was pre-Brexit. I still think the UK is in fact one of the easier Western countries to move to, especially if you can't find moderately paid work
Countries with a national id system I would guess tend to be more difficult overall though. And the UK famously is not one of those.