I don't wonder if this issue with Tempests is because Frigates are finding more use from people in 0.95 whereas they were left by the wayside for most players in 0.9.1 due to Objectives being important to capture and the game including many skill buffs for frigates via Gunner Implant Elite, Coordinated Maneuvers, Wolfpack tactics, and Targeting Analysis. Now that frigates are being used people are putting more focus on the strong outliers the Tempest and Omen, but the main detail to look at is what frigates are best at and what doctrines are best at.
It makes sense that the Omen and Tempest are considered best because High-tech's doctrine of high mobility and burst damage is in line with what a frigate can do best, move quickly into range, flux out and hit the target hard, and then back off and recover. Conversely, Low-tech doctrine of high armor and sustained ballistics doesn't work out so well when you can only have so much armor and guns on you compared to what a Dominator or Onslaught can field. Mid-tech frigates meanwhile might outrun anything larger sure, but its rather hard for say a brawler to strike at arms length when it can get two 1100 range weapons at best compared to capitals fielding many 1600 range (or more with Gauss/ATC) weapons or Eagles and Falcons running them down with many more medium mounts. The Kite is a meme because even though its otherwise very weak, its a 3 DP frigate that can sometimes get close enough with weapons that can really ruin your day. It won't do it very often and more often than not its just a punching bag for all of a second, but you will remember those times when a Kite Reaper gets through your notice and cripples you. Getting close and bursting is something that frigates can do to keep up against late game larger capital and cruiser spam and getting close and bursting is something that the Tempest is able to do regularly thanks to its fast speed, two Medium mounts, and HEF. Anything different and you take it away from what frigates can do to compete.
Its also what makes other stronger frigates considered so strong as well due to their capability to threaten capitals and cruisers, Afflictors, Hyperions, and Scarabs are all very capable of moving themselves into a position and with enough burst power to threaten a capital, the difference is that they have tricks to do so, while Tempest only has its raw speed and so can't strike with as much impunity as the above.
Other frigates that are considered strong or outliers do so in a manner different from the ones that people are most concerned about because they're strong at different things then taking down big ships. Omens, Monitors, and Centurions are great at holding out and taking down missiles/fighters and being a temporary shield to take up something's time. Anything else is considered either too strong because it can effectively hit against something larger than destroyer or forgotten about past the early game because they get taken out too easily by said big ships or their fighter complements while being unable to effectively threaten them. Aside from Afflictor and other phase frigates needing adjustments because their only real threat is getting caught by their target exploding, the Tempest is one of few frigates that's able to keep up with larger ships threat-wise when the main fleets clash together and it seems weird to want to nerf it now that frigates are starting to be something other than road bumps you kinda just run over when you start fighting the enemy fleet.