I do agree that being oncall can be an unpleasant experience, but it's also a motivation to structure your service to not page you in the middle of the night.
Apparently if you write software to their invariably insane and wrong and totally misunderstood specifications they gain the right to bother you every time anything goes wrong with it. Usually it's 100% their own stupid fault.
Whether this happens at 6am, 2pm, 8pm is apparently all your fault and you, as a developer, should not just fix this, sacrifice your time and drop what you're doing, but you are also expected to pay for this.
So let me just say:
2) if you want this, you're paying extra, and sorry to say, but a LOT extra (10% of a month's consultancy rate for 2h + incidents which DO NOT include new features. Furthermore it is expected that 2 out of 3 months you're paying for checking if the monitoring system is working, nothing more. If it is more, price goes up)
3) if you disagree on this, we have contracts, AND labour law that disagrees with your assessment that "SWEs" aren't paid for 9-5 hours.
4) Obviously we can talk about this. But either modifications to software or improvements in general will come at a cost. I'm very willing to discuss, design, implement, even hire a team etc. for you to do this, but we need to understand eachother : it's not free.
I don't know how it works at Google, but I've seen these attitudes often at large companies. And ... euhm ... you can find some other poor victim to pull this crap with.