In my opinion everything hints at the opposite. In the last 1,5 years since GT5:KB18FANI just hope PD has been taking notes and comes out with a great GT6.
* PD removed a bunch of seasonals, although Kaz admitted there is not enough A-spec content. Makes the game even less finished than before, because you know what you had before and now you don't have it anymore. For quite some time since then, the seasonals where very uninspiring.
* PD didn't make good use of the DLC capabilities so far. First we got RM versions of existing cars (but PD called them TC so they could add more inconsistency, rendering the RM function pretty useless). Most reactions here were "wait till the next round of DLC". Same reaction with the few other rounds of DLC. In the meantime all cars have aged 2 more years, and hardly any new cars have been added.
* A major gripe, the communication and interaction with the customer, has not been tackled by PD in any way. Even the opposite: Kaz's twitter account is not used at all for GT5 anymore lately.
* The updates fixed trivial stuff (like wheel changes and menu controls), but the new things they brought do not promise a lot of good for the future (GT6). More collection stuff (new cards, helmets/suits), car wash tickets, repair tickets, restore tickets. Never understood why effort was spent on these tickets. If the engine or chassis repair of 500k credits is too high, then lower the price, instead of one-time handing out tickets. The game only became more inconsistent because of it.
I don't see any sign that they took notes, or any indication that PD will get its act together for GT6. In my opinion (and an opinion is what it is) GT6 -if it ever comes- will be worse than GT5.