It depends on if there will be holes and whether you communicate "externally". If none of these are concerns (for WAL and using SQLite locally, none of these are), it is OK.

To elaborate, for a local app that using WAL, if a transaction committed locally, then reverted *along* with everything afterwards, the app restarts, and it will continue to function as expected, no ill-defined states.

If you use WAL within a quorum, sure, durability is a concern and I think you would be better off to have ways above SQLite to maintain that durability rather than relying on fsync solely (your SSD can break).

Also, to add, WAL mode uses checksum to make sure there is no holes, so even your SSD re-orders writes, I think no hole for your writes is a pretty safe assumption.