Quick read of the documentation, for an XFS filesystem, it seems you can SET the block size larger, but the kernel will only let you mount it if the partition block size is at or smaller than the memory block size. Ubuntu has a memory block size of 4K.
link - https://serverfault.com/questions/246640/mount-xfs-partition-with-4k-block-size
If you need it higher, you'd need to compile your own kernel or find a kernel with larger memory block size.
If you have spinning disks for your SQL instance, you will want the block size as large as possible to reduce your random read time. If you have SSD's or flash storage, I THINK the block size is less relevant as the disk controller has "magic" baked into it so even if your OS requests sectors 1 through 10, on a spinning disk these are going to be sequential on the physical disk. On SSD's they may not be (or so is my understanding). On SSD's they MIGHT be on the same physical chip or it may be spread out across all of the memory chips.
And if you have hardware RAID set up, the request to read or write from blocks 1-10 (again, as an example) may exist on one single disk OR may span multiple disks. The RAID controller and your RAID setup may do some magic on the back end to get you better performance for sequential reads.
NOTE - I know it isn't "Magic" that happens, but it is something that is transparent to the application and (generally) not conrollable by the DBA.
The above is all just my opinion on what you should do.
As with all advice you find on a random internet forum - you shouldn't blindly follow it. Always test on a test server to see if there is negative side effects before making changes to live!