Doing OLTP writes into a columnar storage is pretty complex. Also columnar storage needs to be in memory or on SSD at least, not HDD where read performance woul

Doing OLTP writes into a columnar storage is pretty complex. Also columnar storage needs to be in memory or on SSD at least, not HDD where read performance would be abysmal without serious gymnastics (thus in particular, given the RAM and SSD prices back then, you just couldn't really have a columnar db widespread adoption 15+ years ago).