Well firstly,I really don't know if you are a core English person or if English is your regular language (no offence) but I believe forum or community is a better fit for thid context than environment. However with respect to you point, lost coins simply means that the owner of that particular wallet lost his keys and his seed phrase. Which literally means there's no possible way of spending the coins in that wallet. Although it actually isn't a donation to the network, but it's literally similar to burning your coins.

To burn  some coins you send them to an address which you lost the keys and seed meaning there is actually no way to access or the coins.Lost coins are actually beneficial to the bitcoin network because it preserves price since it's like an anonymous HODLer is hodling indefinitely causing circulating supply to reduce increasing price.