I think this can just be summarized to "write any HDL like you are modeling real hardware." Both VHDL and Systemverilog were primarily intended for validation and synthesis is a second class citizen.

There is a trend among programmers to assume that everything supported by the syntax can be done. This is not even true in C++, but it's something people think. If you are writing synthesizable SystemVerilog, only a small subset of the language used in a particular set of ways works. You have to resist the urge to get too clever (in some ways, but in other ways you can get extremely clever with it).

I thought that if you have some idea about how hardware works, it is kind of more or less obvious whether something is synthesizable or not.

I haven't learned Verilog, only VHDL and even that with the explicit <register>_ff <= <register_nxt> pattern when I need flips flops and I never felt like there is anything difficult about VHDL

Is the North American insistence on teaching Verilog what's setting up students for failure since Verilog looks a bit more like a sequential programming language at first glance?

VHDL is based on Ada, so it also inherits from sequential programming models.