In his Thomas & Friends series, Plarail followed the market and TV Show and released Thomas & Friends trains for many years. Even now, Takara Tomy is releasing them, and announces interesting new releases. Only in Japan, an entire army of fans wants to buy those trains. That's a very important factor.
True, there are some Thomas & Friends engines and trains that Tomy didn’t make, although we would all love for Tomy to make them, but that’s an old story. Nothing should surprise us, however: we see, for example, that Bachmann soon releases Daisy in H0. Maybe Tomy will also surprise us with some such release of some old friend. You never know.
On the other hand, if there are no more Thomas & Friends new episodes over the years, except in AEG format, they will probably, for market reasons, also start releasing AEG engines - because
what else could they do if there are no new non-AEGs characters? Possibly they'll give up on that series. We don’t know what the medium-term future holds, let alone the distant one. No "educated guesses" help here.
In any case, Takara Tomy has launched many Thomas & Friends trains and sets, they are announcing new ones and - they will not suddenly disappear. They are here. So everyone can and will have what they want: both AEG and non-AEG Thomas & Friends locomotives, trains and sets. What more could one want?
Unfortunately, I don't know where to find the SKU numbers of the listed products.