I do agree with the part on Bounties and airdrops, I am not that convinced on the exchange part. While it is formally true that exhcnages don't add value but allow for exchange of value, we have to admit that in the current crypto scene being added to several exchanges (where some are better than others) gives coin credibility, popularity and a general belief that the coin is worth something. So as a matter of fact it adds value, moreover if your coin has value but there are no ways to buy it (exchanges) this value will never be reflected in a price increase (price that is by the way calculated as the average between exhcanges that list the coin)
If a coin/token has value, there will always be a way to obtain it. That's part of what gives it value. Exchanges are not how everyone should be thinking about obtaining the coin/token.
For example, If I live in England and I can exchange goods and services for British Pounds then I care very little about exchanging my Pounds for Japanese Yen until I visit Japan. The problem is people are creating their own "British Pounds" but there is no England! then they want to be able to exchange the Pounds for Yen and wonder why everyone is dumping the Pounds they created for Yen instead of HODLING and waiting for an "England" to be created.
I'm saying Build England then use your Pounds in England first, this creates value.....then exchange for Yen.
Exchanges do not give a coin/token credibility, it gives the coin/token visibility and yes popularity, but that is not always a good thing for the coin/token because it leads to volatility which is bad for any currency.