Digital scarcity
Bitcoin brought a way to transfer a digital asset through a shared network without a central issuer. Its supply and transaction rules are part of what distinguishes it from ordinary bank balances.
Programs and tokens
Other blockchains support applications and assets with different rules. Owning a token is not automatically equivalent to owning shares or a claim on a business.
Stable does not mean risk-free
Stablecoins aim to track a reference value. Their backing, redemption arrangements and issuer or protocol risks need to be understood separately from the price they try to maintain.
The common thread
Ask what the asset does, what rights it gives you, how it is held and who could fail. Popularity and technical novelty cannot answer those questions on their own.
Further reading
Personal view only. Not investment advice. I may hold assets discussed, and my views or holdings may change. This is not a recommendation or a complete investment assessment.