The only thing you listed that could be described as particularly inconsistent is spelling. But non-phonemic spelling is found in countless other languages and doesn't really hamper the language. It might even be helpful for languages with diverse accents. English could be revised on some points with no issue (, and some other cases), but overall it's functional.

As for the rest, I don't know how phonetics could be inconsistent. Like, is it inconsistent that frogs is pronounced as /frogz/, but clocks as /kloks/, so the -s plural ending is realised differently in different words? As for grammar, what about it? Do you think it's unusual for a language to have "irregular" forms such as buy-bought rather than *buyed? Tons of languages have them, I doubt if there's any without "irregularities" at all.

(Note: syntax is a part of grammar.)

Viewing these things as a shitshow, as something particularly negative or even harmful, is literally anti-scientific.