Because you quote occam's razor then give no simple direct mechanism of action. There is a big gap in how a few degrees average heat increase causes mood disord

Because you quote occam's razor then give no simple direct mechanism of action. There is a big gap in how a few degrees average heat increase causes mood disorders. It's more likely, for example, the result of the ten's of thousands of unregulated synthetic chemicals produced, some of which are hormone analogues like PHB and which make their way into the water sources. Then since they're not regulated no one filters them out or monitors their levels regularly.