Numbers Don't Tell The Whole Story
Since we are back to comparing yesteryear with today, numbers don't really work that well. The F-105D was designed for one primary purpose, the supersonic, low altitude penetration to deliver a single tossed, internally carried nuclear bomb. The emphasis was placed on low-altitude speed and flight characteristics, range and payload. Traditional fighter attributes such as maneuverability were a secondary consideration. Initial F-105Ds were based in Europe, within range of intended targets, generally flat terrain and open spaces. McNamara, upon coming to power, determined that the F-105 has only a single mission capability, failed to meet criteria for integrative enhancement of flexible force structure, and was non-cost-effective. Then came Vietnam.
Since assets to bomb Vietnam targets were minimal (the B-52s were limited to strategic retaliation against the USSR), F-105Ds were moved from Europe to the Far East. when there, the aircraft's offensive capabilities were sarcastically referred to as a "Triple Threat" — it could bomb you, strafe you, or fall on you. You don't need a degree in aeronautics to figure it out. Lose power in an F-105 and it will fall out of the sky like a rock. Hang a full load of ordnance under its wings and it won’t climb very high. Point its nose at the ground, and it will dive like a lawn dart. At that time, on the Howdy Doody Kiddies Show, there was a character by the name of Chief Thunderthud. It had a nice ring to it. Thunder THUD. Thud, as in the noise made by a large heavy object hitting the ground. So, the F-105 became the Thunderthud, and finally, in life and legend, just The Thud. There is no disrespect here. The name came from the pilots that flew them and mused in the club afterward what an appropriate name might be. 334 of 833 procured were lost over Vietnam. The F-105Ds had teething problems as well, in fact twice the entire fleet was grounded for engine failures and fuel flow problems in '61/'62. It took until '67 to fully resolve the engine problems.
As to area rules which have been credited for fantastic F-105D performance, OK465 explained the real area rules quite well.
There were three 'area rules' that applied to the F-105.
1) It took an inordinate amount of 'geographic area' to turn it around (7.33 corner was somewhere around 500 with reasonably negative SEP))
2) It was able to leave a 'geographic area' straight-ahead at an inordinately high speed in its early days (later on not so much)
3) It took quite a large 'geographic area' to build a runway long enough for it to get airborne (even with its water injection system)
1) and 2) limited the F-105d effectiveness in missions over Vietnam. Not only that, The F-105D turned too slowly to reliably beat the Russian-made MiG-21, the Thunderthud's main potential rival at the time. So the USAF received from the Israeli Government an MIG-21 to look at tactics for survival. What was learned was that encountering a MiG-21, the F-105 crew should try to flee, the testers advised. If the F-105 was behind the MiG-21 and the MiG flier didn’t know it, the Thunderchief crew could attempt a high-speed ambush.
But when the F-105 and MiG-21 started out in equal and opposite positions, the F-105 was in trouble. “If the F-105 attacker attempts a prolonged maneuvering engagement, it becomes vulnerable to follow-up attacks as the offensive situation deteriorates due to loss of energy and maneuvering potential,” the Air Force reported.
Comparing the F-35A to the F-105D by means of numbers and area rules isn't the whole story to conclude the F-105D is either equal to or better than an F-35A.
The F-35A's perceived lack of fighter maneuverability, yet to be fully determined, should be more than mitigated in air to air situations by its stand off electronic capability, situational awareness and communications with accompanying aircraft, at least I would hope so.