Based on the fact that it's not representative. That in itself makes it a bad platform for fdev to listen to their playerbase (which it does not represent).
Fact is that the forum is the
official platform for ED. Every player can join and express their opinion here. Therefore, it is representative, given the assumption that the people who do not express their opinion are happy with the game as it is and neither agree or disagree with the development of the game.
There are more accurate ways to evaluate the players' sentiment (such as in-game surveys) but they are not available and perhaps they do not much deviate from the forum opinions.
Bottom line is that the forum is what FDev created for the player base and why they pay a community manager. Other platforms (Steam, Reddit) are probably being monitored but FDev gets less accurate sentiment from those.
Back to topic again:
The technical feasibility of ship
interiors has long been proven by the fact that they (partially) already
exist! The cockpit and the SRV bay are modeled and textured and
exist. Space legs, station interiors, carriers interiors
exist and have game loops. Therefore the statements that full or extended ship interiors (beyond accessing the cockpit) are
impossible are simply disproven by above fact.
The OP's point is: are they coming or not? And this depends if FDev makes a decision to create them based on an ROI calculation. And that calculation influences which game loops and level of detail the interiors would get.