I work for one of the companies on that list and can attest we still use smalltalk/pharo.
of course, learning how to use it properly might take a little longer :-)
You need to know more method signatures to write any program in it. For example things like: someCollection do: [ :someArgument | "some code" ]. Stuff like that. It's still a lot less than most languages though.
I found that this really helps [1] and I find it more representative of how difficult the language actually is. The postcard example is a bit contrived.
[1] https://gist.github.com/jdevoo/8e8866cd6087e05790841d0f20b2e...