A couple of years ago I was at Protivin station in the Czech Republic when I grabbed a photo of the train I'd just alighted only to realise I was suddenly on a narrow slipway with two moving trains either side.
I managed to do that once in Slovakia - fortunately without having trains moving on the other side.
I was in Hungary recently, at Tiszafured there were no fences or barriers, when the train was coming people simply walked across the tracks to the appropriate platform. More major stations had underpasses although some people still walked across the line.
I then got the train to Revnice to visit Pivovar Revnice. I used the subway to get from the platform to the station exit. When I returned later on the train back to Prague arrived on a track without a proper platform. It was a slightly raised block of concrete that was accessed by walking over other tracks!
There must have been a time when many stations in Europe - even quite major ones - worked by having the area by the station building being the waiting area, with the other platforms (or piled up ballast) just being used to board and alight. As your train came in you walked across as many tracks as required to get on.
This is of course a bit awkward if there are two trains in at once, and also requires some care from trains running through non-stop when it's dark or foggy.
I presume this all works fairly well with the system of having the "station master" also being the signaller.
There are still plenty of stations in Czechia (and indeed some within Prague itself) that work like this though from what I've seen it's now confined to smaller or less busy ones.
On a trip from Prague to Linz a few years ago I saw a few stations like this across the Austrian border, and more that had been rebuilt with subways.
As in this design you board trains from a platform at the station building side of each track, an obvious feature is that there is generally one track rather than two between each platform, and I've seen stations in various Western European countries with this configuration but with "proper" platforms, either with a subway or a single foot crossing rather than a more free-form approach to where you cross the track.
Here's an example in Czechia:
This one is in Spain, with "high" platforms and notices warning you that you really ought to be a bit careful when crossing the tracks. Maybe it once looked more like the one above.
And as for fencing, I was intrigued on a recent trip through Belgium not so much by the large stretches of unfenced track (that's pretty common in much of Europe) but by the fact that on the high speed line some of the fencing was just mesh held up by wooden fence posts. Not how we'd do it in the UK...