a crypto without being inside a blockchain is less secure than the ones that is there?
There are other technologies other than blockchain. Some of them are not secure. For example, IOTA uses tangle but it had huge security problems. You can read it here:
https://bitcointalk.org/?topic=5227016.0There are others, like Hashgraph as well. Like
hedera , currently 34 on CMC. But, will it sustain?
blockchain is the most secure and tested technology for cryptocurrencies.