Yeah, the profit for a scalper is probably about $100-$125 on a system that sells on Ebay for $750 in the US.  So, if supply and demand just get a little closer together, such that secondary market prices fall by $100, that should squeeze out many of the scalpers.  They'd still be able to make money selling locally where they don't have to give Ebay a cut, so scalping wouldn't be eliminated.  But, we'd definitely see a whole lot less of it.  

There are far more chips produced than Sony or MS need.  They don't need all chips, they just need more.  So, they just need to get a tiny bit larger piece of the pie, and I'm sure they can pay their way to that.  

Sculptors will stop sculpting if you switch their right-hand-hammer to a left-hand-hammer.

TSMC has contracts to uphold with every of their customers and their capacities are 100% booked for years in advance (probably already overbooked).

Half a year ago they were only taking new orders for 2nd half-2022:

TSMC chip manufacturing capacity is fully booked through the 1st half of 2022, and was booked based on client order history and projections of end-demand to avoid overbooking, media report. TSMC will take orders for 2nd half-2022 in late 2Q this year. $TSM #semiconductor

— Dan Nystedt (@dnystedt) March 22, 2021

Now they are probably taking orders for 1st half-2023.

So which contract should TSMC break in favor of MS + Sony?

And how much money from MS + Sony would weight up the costs (penalties for breach of contract, costs for adapting the production lines...) and bad reputation (unreliable contract partner)?

Well now you know I'm genuine!

I don't have an answer to the question about how much money it would take. But, we all know that there is some number. Contracts are amended and canceled all the time.  Money typical changes hands for that.  And, that's the point of the OP. It's a hypothetical.  I think we all agree it is unlikely to come to pass, for a handful of reasons.

We'd see shortages regardless of the price and in the long term, it could result in fewer systems on the market. Software is where those companies make real money. The more systems are out there the better. Also, keep in mind, that they would have to cross the psychological barrier of $500.

I don't think its worth the PR storm they'd ensue from raising the price. I think it was cause many not to get one until they'd be discounted long ways down the line

Do you serious think if they raised the price to $10,000 you would see shortages?