Nevermind, looks like MobaXterm shell provides a non-standard curl implementation:

$ which curl

curl: aliased to _tob curl

After installing curl with apt-get it works.

I hate it when people do that. You can wonder for hours why something obvious doesn't work as it should and in the end discover someone decided to implement something substandard, often for no good reason.

Especially curl. https://daniel.haxx.se/blog/2021/05/20/i-could-rewrite-curl/

that's every distro and *nix derivation

Well, Windows too. I recently had to set up something simple on a Windows 10 machine, I quickly checked by tab-completion if a python binary is available so I copied by setup script only to discover someone smart decided to redirect the binary to the Windows Store. Yes, I know the rationale behind this, but still. Just like hijacking nxdomain.

And powershell!