My understanding is that free tier is awesome but if you have (for example) a massive traffic spike there's no real way to avoid paying for all the egress unless you go cap in hand to AWS support (who, to be fair, are usually pretty reasonable).

There are some mitigating things you can do, set limits on various resources and billing / budgeting alerts but fundamentally I don't think there's an easy way to avoid being on the hook for unexpected costs.

Theoretically you could have lambdas that react to billing alerts and shut things down but I've never seen anyone set that up.

Seeing as the free tier only lasts for a year, it seems fair to discount it. If it was free in perpetuity (below some use threshold) that'd be one thing, but it isn't.