Leave high TC job vs cofound a tier-1 VC Funded Startup? I will not promote

Hi all, been troubled with a tough decision recently and wanted some advice from you all. I currently make a fair amount at a big tech (think half a mil or more). We (cofounders) were reached out by some tier-1 VCs and they are interested in funding us (couple Ms) directly into seed round (not caring about idea, just investing in the people). We have some ideas but nothing super strong (without going into specific it's something AI native SaaS) and if anything it sounds ambitious but very much unvalidated/verified and high risks to GTM, etc. If we are to pursue the startup founding, we likely will try to work with some potential companies and connections who are founders to get a better understanding of what they want, and slowly pivot or work to get something that they for sure want. But at the end of the day, it's pre-product, and in some ways you can say it's pre-idea. I am sure a lot of folks would genuinely kill to be in this position, but I feel really torn. For me, the main thing is career growth and financial stability im giving up (founders ofc cannot pay themselves super well, likely 100-200k vs my current, their millions of funding are to be used for scaling the company). I am still quite young and don't have anything tied down so just losing a few years of high income pay (probably 300k+ difference) & if startup fails, the possibility that I won't be able to easily bounce back to my current position (I do research rather than SWE work, so a few years disconnected from the field can be quite bad). Does anyone have any advice? Not to sway it one way or the other, but what are the more important questions I should ask myself here and things to consider to make this decision? And if anyone had a similar past (e.g. high income, got vc funded startup), would also be great to hear what your thought process was. Thanks all! Really appreciate it!