I remember watching a documentary on assisted suicide where they said that many people who are approved never follow through, but knowing they have a way out provides a great deal of relief.
With that in mind, I can easily see how things like fences might make the problem worse as you said. People will feel even more trapped and helpless when what they need is the opposite.
Heightened suicide risk is often short term and situation specific.
I didn't say this (because I thought it was obvious) but installing fences is not meant to make people happier. It's meant to reduce access to means and methods. This is part, but only part, of preventing suicide.
It's a very important part, and it's the bit that we have best evidence for.
In the short term it's the bit that has most impact.
Heightened suicide risk is often both _short term_ and _situation specific_. Access to support at this time can save lives. People cannot access support if they're dead, so alongside providing immediate support you also need to reduce access to means and methods.
I've never claimed that the only thing we need to do is install fences.
With that in mind, I can easily see how things like fences might make the problem worse as you said. People will feel even more trapped and helpless when what they need is the opposite.