One of the fundamental duties of a solutions architect is to control the technical complexity. If you don't instead of getting pools of expertise and pockets of ignorance you mostly get pools of ignorance.
Hybrid cloud means there is more than one thing but different enough to require more knowledge as to how to secure, maintain and develop in it.
Forget egress charges. Even if horrendous it pales into insignificance next to the duplication of effort required for the extra staff and staff time to look after it.
CFO Long pockets is going to hate waiting for their staff to produce a cost for cloud report.
The quarterly visit from the auditors, what fun. If you automate the collation of information for the auditors in one cloud then you'll have to do it all over again but differently in another because the mechanisms for doing so are different.
Let's suppose you've gone multicloud for the shiny-shiny. All the gear and no idea! How does that translate into better customer experience, retention and sales?
Multicloud means multi feudal kingdoms.
Basically multicloud is a massive CTO egowank