I’d suggest it depends on your hardware setup. If you have sufficient disks and care about availability and/or performance of your data access, RAID is rarely a bad idea.

If you choose to do a software RAID in Linux without Intel RST, you have three main options: mdadm, LVM, and ZFS. You can explore those options on your own, but my personal view is that ZFS is wonderful to work with and comes with tons of benefits itself alongside its ZRAID implementation, making it my preferred choice.

edit: I forgot btrfs! I have no experience of it but I imagine its RAID implementation is as similarly awesome as ZFS/ZRAID.