I think most people have improved the same way as you this year. Generally its a lot harder to get the top results, a lot less room for errors etc. A lot of teams are doing better work with setups/practicing smarter, not just yourselves. Standing still relatively is work in itself over the last year, atleast for us.
Id say Vires have improved more on the setup side, before I had them down as people who could do much better if they put their mind to it/worked with setups. Maybe thats just my perception and I'm wrong. Also obviously as a team they have moved forward, before they were more like individuals wheras this year they seem to have a more community feel. So like you say, results/performance isn't everything. It's just my opinion but even if you wouldn't vote a team like vires, then there are still other teams(nFinity ofc, didnt think of them before!) who were almost nothing at the start of the year, so obviously they are able to improve more. I've improved a lot as a driver this year, attitude/setup work/pace - just like last year too but I didn't get nominated for most improved and won't again this year because improving alone isn't enough.
Hope that makes sense as I didn't intend to cause an offense with what I said. Like you said, the community awards are only supposed to reflect what the community thinks, not necessarily the truth and it struggles to even do that due to people voting for/against people they like/dont like rather than objectively.