Obviously these things are subjective, but a plaza is not a replacement for a park to me - neither is an area with two dozen or so trees, I need to be able to escape into a little bit of nature every now and then
The sea is definetely a big plus, but also not a park replacement - I think pointing out it's lack of a proper green area is a fair criticism, especially given the tone of the original tweet which acts like this is the peak of human living
I'd argue the only people who don't need a park are ones that have enough room that it's redundant. Where do children run around and play? Where can you throw a ball or frisbee around or fly a kite or have a picnic etc but a park