Are some languages easier to learn? (A twist on language superiority, improvement, etc.)

I tend to believe that some natlangs are easier to learn as foreign
languages for adult persons.

Does anyone agree on this?

Does anyone think that there are absolute criteria on what kind of L2
linguistic structures are easier to learn for adults (irrespective of their
L1, that is)?

If yes, which are these criteria?

Obviously I have my ideas, but I want to see what others think.

/BP


B.Philip. Jonsson <bpj@...>

Solitudinem faciunt pacem appellant (Tacitus)
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