Hmm that seems quite strange to me to be fair. So everybody who sent an unconfirmed transaction will still be in control of the coins on the forked chain?
Depending on the fork, and whether it has replay protection or not, it is possible that the transaction could become confirmed on BOTH forks. In either case, the most recent confirmed transaction on a given fork will determine which address has control of the coins on that fork.
So if I understand correctly dedicating hash power to the forked chain is rather pointless because right after the fork there's nothing to mine?
There is the block subsidy. Transaction fees would need to wait for users to start sending transactions that are valid on that fork. However, the subsidy is still the majority of revenue per block for most (all?) bitcoin forks.