Only a cynic who has no idea about the training regime, which is already largely standardised across TOCs, and is controlled and monitored by the ORR. It has nothing to do with “union pressure”.
This is something you’ve just made up and, from the perspective of someone involved with driver training, is laughably divorced from reality. The training is lengthy because it needs to be, and delays tend to be due to - surprise surprise - shortages of instructors, limited training school capacity etc. It certainly isn’t being slowed down by unions.
In fact the union where I am is currently raising concerns about how long it’s taking to train up newly recruited qualified drivers due to various internal cock ups.