You can have a monolith and still suffer form these problems and need these technologies, as soon as you introduce a load balancer.
Strong module boundaries
Independent deployment
Technology diversity
And with a single database you severely limit the benefits from strong module boundaries and independent deployments. Suddenly you have to synchronize deployments, and anyone can pull or change any data in the database which now must be enforced with discipline which gets you into the same boat as a monolith.
Only worse because you don't have tools (IDEs, linters, etc) telling you what parts of the code have to be changed.