A lot of people here seem to misunderstand this post. What the op is saying in essence is that invest what you can afford. If you can afford 1 Bitcoin get it, if you can't buy what you can.
So many people can't buy 1btc at the moment unless you are extremely rich so Op is Right
Even for me, I can misunderstand it easily if not because of this post. It is because that is what the title is implying but I like that there is a twist there, only to make things more exciting. Investing what we can afford is already common though. It is also obvious that buying 1 BTC now is hard due to the expensive value of BTC but we still can slowly accumulate as a budget user and we might still reach 1 BTC in the future if we are consistent with it. If we can afford 1 BTC, it does not also mean that we will immediately get it, because what if we don't have a strong interest with it? We might only end up regretting after seeing the value of it goes down quickly.
This advice is great because a lot of people want to invest but they feel buying little fraction of it is too small. For me, I don't think is small.
Yes it isn't, due to the expensive price of BTC. This is why people always regret that they didn't join early when the price rise even more.