Maybe. Probably.
It sure looks like the spalling exposed some rebar, which appears to have corroded. It also looks like there might be insufficient “cover” in some of those locations. Some of the other photos look bad, but are mostly cosmetic.
Looking at the original structural framing plans, it’s all mild steel, no post-tensioning, which would make sense for that era, and it doesn’t “look” to be over-reinforced. In other words, the failure should have begun with plastic deformation of the reinforcing bar, not with a sudden compressive failure of the concrete.
IE, there should have been (and may have been) signs of imminent failure. We won’t find one single point of failure, but a long chain of contributing factors, imho.
We won’t find one single point of failure,
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The video of the collapse indicates that the center section closest to the pool dropped first... but the rest of the building dropped straight down almost immediately after. Then about 10 seconds later, the ocean side section went down and it followed the same pattern of the south (pool) side dropping first to be followed almost immediately by the rest of the building....so that in both cases, both sections essentially came straight down. What that tells me is that the entire support structure was weak as stink but in all cases of failures, something goes first and in this case, it was the support structure closest to the pool that let loose first. Since the rest was already weak (overloaded) the transfer of load put it over the top and down it came.
I have a friend who lived exactly where that condominium sits today back in the early 80’s. He said that they wanted to build a drug store on that location but the building application was turned down because the geologic conditions were too unstable to build there.
Buildings that are built on a sandy soil will have their foundations supported by deep piers. Underground there was the water table from the ocean. That water table was the issue in the earlier permit application. Salt water can penetrate concrete and slowly cause it to break down, as well as eating into any underlying metal reinforcements used inside the concrete. This will cause the building to settle, causing strains on the structure.
How this condominium was built there is the big question.