If there is some insurmountable reason why the entire collector canopy has to be replaced every 4 years (at half the cost of the original Collector system), that does significantly change the calculation. T5 also says that Tech 14 Collectors can only hold enough power for a Jump 1. And Tech 15 for a Jump 2 and so on. Collectors under the T5 rules would be a lot more problematic. They still would be useless for the military. The commercial case gets a lot trickier, too. A Collector on a large freighter would still be profitable, but the replacement costs of the canopy would eat half that profit. And the lack of high jump capability undermines the best use case significantly, especially on the frontiers where T14/T15 starports to build/replace the collectors are few and far between. Probably only get used in high tech clusters or by exploration ships that don't want to rely on jumping only to systems with fuel sources.
Btw, the Annic Nova is at least a Tech 16 ship since it has Jump 3 capability in T5. But then the collectors on the Annic Nova can replace the power plant, which MgT and T5 ones can't. Annic Nova Collectors also have recharge rates based on how close they are to the nearest star and how bright it is, which doesn't appear to be a feature of MgT or T5 Collectors.
But, then T5 is pretty substantially different from other Traveller rules in general. For example, the rules for fuel scoops in T5 are substantially different than in Mongoose Traveller. Fuel Scoops + Fuel Purifier in T5 can purify 100 tons of gas per hour with a 1 Ton purifier. Compared to MgT's 20 tons of fuel per day per ton of purifier. But T5 also requires a different kind of intake system if using water or ice as the unrefined source...
It also has weird things like needing transfer pumps to move fuel from a drop tank to the power plant, though there is no such requirement for doing so with on board fuel tankage.