Am not underestimating your capacity of giving up to $500 as reward to winner on this, but I consider it more of a project research work which shouldn't involve money to earn since it's not like a normal contest everyone will take his time in applying to be eligible for win, I may be wrong though, but we have to offer things that will go far beyond the reasonable doubts of other people concerned, and if it's as exactly how being said, then I give applaud to their efforts and contributions towards this research.
I'm not sure I understand your point, are you perhaps against incentivizing research participation? I think it has its pros and cons which makes it a very debatable topic.
In any case, I doubt OP would reach this many submissions at the same time frame if there was no incentive. No incentive does not necessarily mean no one will be filling out lazy ass answers either though you could say, with-incentive participation is more susceptible to abuse like multi-accounting. For starters, op may wanna reconsider entries from low ranks 🤔 -- including on other forums as well e.g. altcoinstalks
For me, I don't consider this an incentive it's just prop to encourage or attract the community to answer the survey. It's true that without this raffle or prize, likely no one would participate or respond to the survey. I hope the distribution of prizes changes; it would be great if it's not just one person who wins. It would be ideal if the winners could be divided into five, so that more people would be happy to win. Right?