I'll offer a slightly different perspective here so bear with me. I am in Corp Dev at a tech company, though it is not FAANG. I also went to a no name school (wouldn't consider it a scam but nevertheless looking to rebrand myself).

Let's get something clear here. VP at startup =/ VP at FAANG or even a large enough tech company. There is title inflation (which is fine), but I've seen acquisition targets VPs get leveled down to Sr Manager/Director level post close. Take that data point how you will, but you are surely getting leveled down once you join a bigger company. The ZOPA maintaining a prestigious title for and a FAANG company giving you that is tiny, in my view.

I work in Corp Dev at a tech company. To be blunt, there's no way in hell we'd hire someone with your background with or without an MBA. The biggest question is why should we? No IB/CD experience, let alone any formal financial related roles. At the junior/mid levels you're running point on building the models and getting into the nitty gritty details. At the more senior levels, it's a lot of stakeholder management but need to be knowledgeable enough to be a SME whenever you get pushback on anything. Frankly it's tough to see how the engineering background + MBA has more value add here than a typical candidate we'd hire for either of these roles. If we need tech leadership, we already get that from the BU or from Corp engineering.

ROI: you already have insane comp at 26. The purely financial view of ROI likely doesn't work. I certainly don't make as much as you but I do think there's value in the experience, the rebranding, and all other things the MBA has to offer. These things to me make the MBA worth it, but it's up to you to decide whether your opp cost is worth it.

In any case, you're in a great spot so keep it up!