[kangax]

I agree that TS increases barrier to entry for contributors. However, it's very different from Coffeescript. It offers better program correctness via types whereas CS was mostly sugar. Libraries that (properly) use Flow/TS are less likely to have bugs and are safer to contribute to (you're less likely to introduce a bug) and that's a good thing.

[marcus_holmes]

Libraries that (properly) use {{insert anything here}} are less likely to have bugs and are .... etc

remove the (properly) and I'd give the technology some credit. Otherwise it's just "no true Scotsman" fallacy.