I see this posted a lot: that the ships we see now are aggressively dictated to FFG by Disney via LFL Licensing. I'm no longer sure if it's part of this forum's tendency to present wild speculation as confirmed fact or if people actually believe it.
We know a bit from designer interviews: LFL does have a veto power which they do use from time to time: they can and do say no to FFG at least with regards to characters. They've done this since at least Wave 4 and they've let some pretty obscure stuff go through so we don't know what their criteria for saying no are.
As for influencing ship choice, we also know from designer interviews that the CEO of FFG has a lot of influence and that may be why some lesser known ships have been made. But there's nothing to suggest that Disney itself is dictating to FFG which ships to make in some nefarious plot to erase the Legends canon.
The "proof" is supposedly a lack of Legends content but that's simply false. E-wings and TIE phantoms in the most recent Armada expansion, . If Disney are dictating to FFG what to make then explain this: how is the M3-A Scyk, a ship of TIE punisher levels of obscurity, getting a second release in the Scum Epic?
FFG likely makes the newer more publicised ships because they sell better: they've got the numbers on how obscure ship waves sell relative to better known ones. Their best selling ship to date is still the Wave 2 Millenium Falcon because it's so recognisable.