Hi Brandon,
I've been diving less than 2 year so cannot speak to the frequency of good summer conditions. However I did squeeze in 7 dives last June + July, and conditions were OK to good.
Regarding the kelp forests, yes what we are experiencing in Monterey area is bad and trending worse, but up north is way worse. Up there, they have are tracts of urchin barrens measured in tens of kilometers that used to be healthy kelp ecosystems. In Monterey/Pacific Grove/Carmel there are urchin barrens, healthy kelp forests, and the gamut in between.
Down in Carmel: Pt Lobos, Monastery, and Butterfly House were each in good shape, last time I was there. I tried to get to Stillwater Cove just after Covid-19 closures began, but the golf course people wouldn't let me in, even though the cove itself was not actually closed. Jerks. Carmel sites are highly sensitive to conditions, oftentimes I will drive down there, take 1 look at the beach, and then go back to the peninsula
. Great diving though, arguably the best in the area.
In PG/Monterey: Otter's Cove, some of Lover's Point, McAbee, and the Breakwater are reliably divable sites with decent to good health and not very sensitive to conditions. I haven't tried Coral St, but it looks healthy from the street, divable during high tide only due to rocky shore. Pt Lobos is closed, as you mentioned, and its closure is indefinite. I would be surprised (and delighted!) if it opens up in June or July.
Dive shops in the area have been incrementally opening up with variously restricted hours and services. It's a little hard to predict what their status will be 2 months out, but probably
something will be up and running, especially if you're willing to drive a bit. I would plan to call around say the week before to see how things are looking.