If you assume that the survey sample represents those who post on the forum (not unreasonable), we see that more people are on this forum are here because they've played DOS1&2 or DAO versus BG1&2, and 35% (not an insignificant amount) have NOT played 5e. So posters on this forum are not overwhelmingly from BG1&2/old D&D purists. A majority, sure, but also take into account that these players, like me, may have only played BG1&2 in recent years after starting with 5e.
If you look at the answers of only those who are NOT familiar with 5e (assuming that these type of players are the "mainstream" audience Larian is looking for) https://i.imgur.com/KAcSU4N.png, they still dislike e.g., surface effects, increased HP, and stealthing as a bonus action available to everyone.
And look at the language employed by the survey without bias and see if it passes a basic test. It actually doesn't. Beyond that the sample size is fucking terrible so extrapolating data from that is kind of worthless unless we're talking very specific things. And we aren't.
You can also look at the Steam reviews which has a larger sample size and those do not reflect the same sentiments as expressed in the survey.
I think it's very stupid to think that the forum and everyone who partakes in it is representative of anything but the type of people who visit forums which is a subset of the audience that Larian happens to capture ( as you pointed out we have no idea what audience Larian is actually looking for) - we're all pretty special. If you want to talk about the mainstream then the approval rate is 88% on Steam currently with a sample size of 26k which is far higher than any aggregate provided by the shitty survey. It also comes with some kind of standard unlike the survey.
Also, the majority of the posters here do not fucking care about the combat so much as caring for their own class, cosmetics, or narrative aligned things; go ahead, chop down, and reorganize all the threads created by people here organize the threads by user and reduce them down to one theme and you'll most likely find that the majority isn't combat related.
