PollyTickle
How about our language, nicked from many others but we’ve still made more complicated to learn than any other
Bough
Tough
Cough
Though
Poor, pour, paw, pore !!!
Yes, the spelling can be a bit of a nightmare for learners, but other aspects? Verbs hardly conjugate, except for the 3rd person singular, no noun genders to have to learn, no declension of nouns.
Take Russian, for starters - two infinitives for every verb, plus full conjugation, not to mention declension of nouns (3 genders, same as other languages I can think of) and adjectives - six cases!
IMO English makes up for its admittedly tortuous spelling, with the lack of that heavy learning burden in the earlier stages.