>> argue about it in meetings for weeks, bringing only opinions
YUP:
One test is worth a thousand opinions.
(and yes, the entire point of the throw-away version is to test every aspect of the MVP++. And sure, you may keep some chunks of it, but that is sort of based on luck. A big part of the attitude on the initial version is that no one needs to think about technical debt here - it's all a big experiment, done to generate information and data to build a solid foundation.)
Yes. But I'd frame it a different way. The initial implementation is the source of empirical data that you need to formulate a viable plan. You're not building something to "throw it away". You're building something so that all subsequent decisions can be made on a solid foundation.
To be concrete, I've seen teams faced with a technical decision who a) argue about it in meetings for weeks, bringing only opinions and personal experiences to the table vs. b) set up a proof of concept for all options and run benchmarks which can be used to make informed decisions. (a) takes longer and produces an inferior product - I've never seen an exception.