Wait times are now collected only for local purposes. For a while TSA was collecting this info because the data didn't really mean anything. A few airports have wait times all the time, but most airports have low wait times with spikes throughout the day. Those spikes can be predicted but are also related to traffic at airline ticket counters. For example my airport has typically low wait times even when flights are at full capacity, the only time wait times increase is when one airline's ticket counter is slow so that passengers from multiple airlines all arrive at the screening checkpoint at the same time.
This condition is related to weather, airline staffing, passenger composition, etc. Most of the time we have adequate staffing, and we do try to predict wait time spikes. But it winds turning a 8 minute wait into a 24 mintute wait, which is not catastrophic. We do watch passenger loads closely, but really the only true impact on wait times is if the United passengers arrive at the same time as the Southwest passengers which is independent of flight loads.
In any case TSA does not use wait times to justify hiring. Airports are allowed to hire based on the total number of passengers departing from the airport, with some wiggle room that is justified at the national level.
I think TSA recognized that the process needed to be standardized to be effective, however the effort to collect the info was not worth it. If the checkpoint was collecting bad info, it wasn't going to be really used for anything anyway. I think that this is info that passengers may think they want but don't actually use. The effort to make it good data does require work to ensure it is standardized and accurate.
I can tell you as someone who worked as a checkpoint supervisor collecting wait times had a price. It was easy to collect the info when we were slow, but when we were busy I wanted every TSO working to get people through the line and on their way.
This was a long meandering answer. But basically the wait time info is meaningless is my answer.
castro