That is speculation. Other blockchains it was created with block rewards from the start (that's why you mined bitcoin, ethereum, etc. because there was a clear case of rewards. This is why no one wants to be a Ripple Validators at the moment). We do not know if
1. XRP will even get a reward at this point. 2. If it will be the form of a block reward. 3. Even if there is incentive, which is a big if at this point, don't expect much out of it for running 3 servers. Ripple been out for years.
LDSR should be running validators because it wants to help the Ripple network and believe in its mission. Not because they think there is a pot of gold at the end of the tunnel.
If block reward refers to validators getting XRP then no this will never happen. Bitcoin has a reward system for mining because the coins are locked away and need to be freed which requires computational resources. Ripple pre-mined ALL XRP. So there is no need for mining. Validators exist to increase decentralization and to keep the process active in the event Ripple the company fails.
All this validator payment nonsense should stop. The rewards are this: notoriety for being on their UNL list, voting privileges on changes to transaction costs, voting privileges on reserve requirements.