Oracle will let the ticket bounce around Tier 1 asking you basic questions for months until you just give up, just like every other vendor.
Sure, we've had our reps bring in pizza and beer during huge Oracle downtimes, but they never actually SOLVE anything. "Escalation" means "get a manager really mad at the poor support person", not "give it to somebody who knows what they're doing", because those support orgs don't have those people anymore.
OTOH, Oracle knows you're not about to stop your business for a year or two so you can figure out how to migrate a 150TB DB, and figure out how every little piece of code written over the past decade or two will handle the migration to different software.
What are they getting paid for then? They take the TPS reports from the in-house engineers to the Oracle managers? They're people people?
You get very wildly different levels of skill, and many times very low levels of skill. Then they hire consultants, because we can make the thing go.