1. Relying on unregulated infrastructure and exchanges is risky;
2. Regulators are cracking down;
5. Many central banks might issue digitial currency, posing a threat to the non-government tokens.
neither of these two are new. things have always been like this, exchanges from the small ones in early days that we have forgotten the name of, to big exchanges like Mt Gox and Bitfinex have always been risky.
as for 2, there are a lot of regulators that are friendly towards bitcoin and helping it grow in their country! so that is not a reason.
3. Cryptocurrencies are managed by communities of developers, which can get messy. For example, BCH's hardfork, BCHABC and BCHSV, are causing chaos in crypto market;
i wouldn't call them "communities of developers" because there aren't exactly developers behind these forks but greedy people who are thirsting for power and money.
in case you have forgotten, bitcoin is money and money is power. a lot of people want to take control of that power hence the existence of these forks trying to fool people into thinking they are bitcoin since they couldn't compromise the real bitcoin!
4. ETH and other cryptos encounter difficulty in their network, making their tokens hard to be used in the reality world.
nobody cares about what happens with altcoins! historically speaking their dumps sometimes might have affected bitcoin price but they can never make enough influence to be considered a thing.