How should one deal with offer being rescinded?

Have heard about some offers being rescinded from Meta and Uber. Wanted to interview there, primarily for fast paced growth and excellent folks around, but hearing about offers getting retracted, seems like a risky bet!

Should one keep multiple offers till a week before the joining date as a safety net?

More options are always good! An important lesson is "Never declare victory early" - Don't tell your other offers that you decided to go somewhere else unless you absolutely have to. It's not over until you start at the new company.

What are the steps one can take when an offer gets rescinded?

Unfortunately, I don't think there's anything different here about another case of being unemployed - You'll just have to get back to the grind. And of course, if you have other offers still on the table, follow up on those.

1 thing I will recommend though is make a post on LinkedIn about it. I have a lot of problems with LinkedIn, but it has a huge amount of empathy for these cases (at least from what I can tell from my LinkedIn news feed), so you'll probably be able to get some sympathetic referral/recruiter leads there.

Hey Alex, Wanted to understand if holding multiple offers until the end of your notice period is okay. If we are asked to give a Yes/No, should we say Yes for one and later back out once we join the organisation we want to. Thinking if the company to whom we say No later, can pose some legal concerns at us if that happens. If not, I think that could be one way to safeguard ourselves from offers being rescinded.

Is the idea that you say "Yes" to multiple offers to keep all of these leads warm and when you finally choose the organization you want, you flip the ones you didn't choose to "No"?

If that's the idea, I strongly don't recommend it. That's called "reneging" IIRC, and that will greatly erode the trust you have with that company. Lying in general is bad, and companies already treat candidates poorly enough - We don't want to ruin the "Tragedy of the Commons" by giving them another reason to not trust us.