After running through the poll Jagex definitely appears to be operating solo on this one. No third party firm would allow participants directly enter in their contact info (because it would mean they'd lose your business to their customer [so not a nefarious thing]) and also the only area I found kinda strange was that the telephone number request at the conclusion. I would have substituted that using a check box for recontacting and pipe-in the email that you could optionally have put in earlier for confirmation. I think you are fine answering this questionnaire when you have privacy concerns since essentially all information is unknown and it's using an industry-standard platform of Qualtrics. Jagex probably does not have market study ISO certificates but this is a quick yearly survey so they would not need to have any.
I hope this feedback encourages the staff to make surveys more concentrated to the audience who actively take part in the content they're polling, or use them as an advisory tool instead of a judgment. It would be interesting if they reveal some of the results of this survey. I answered the precise contrary, that polling is at the core of OSRS and they should stick with it strictly. For clarity, I answered that polling is in the core of OSRS. The poll system empowers the whole playerbase to start freeform discussion on the planned changes/additions created to Runescape itself and it is absolutely a terrific way to gather feedback and public opinion on something. That said, I really don't think the current format satisfies the best interests of Runescape.
I really don't believe the participant base is particularly good at determining which material, based on objective virtue, is good for integrity and the health of Runescape long-term. We see people vote based on self interest. Based on polling, NMZ was enjoyed by the community but it was important to remove despite that, that Jagex did. Players do not vote for any changes which make things harder for them but over time that becomes a drawback as material becomes simpler and achievements are diluted, these are very slight but easily add up.
Another example is PvP and PK adjustments that are consistently voted against. People even voted against letting pures wear chaps. The impact of the to accounts will have been to boost the need and therefore improve profits from hint scrolls. This isn't an illustration of polling meeting the interests of Runescape, it is only a meme of not enjoying pures. If we only see updates that match the exact same 75% of individuals every time the remaining 25% become more and more marginalised, which isn't a fantastic balance when people 75/25 are seemingly so frequently the same people.