Cleric in full plate can also wear a tower shield (or large at least.) They have the divine power spell as well for full BAB. If they are a melee cleric then they will likely run in something that grants more PRR. These are all available to even a pure cleric:
Warpriest enhancements
Wall of Steel +3/+6/+10 Physical Resistance Rating
Sanctuary For 20 seconds, you gain +20 Sacred bonus to Physical Resistance. (Activation Cost: 10 Spell Points. Cooldown: 1 minute)
Legendary Shield Mastery, an Unyielding Sentinel's tier 2 ability, improves PRR by 5 per rank when wearing a shield. 3 ranks total, higher ranks require (Improved) Shield Mastery.
Heed No Pain, the Unyielding Sentinel's level 4 innate ability, improves PRR by 10 and grants 20 additional physical resistance while in Unbreakable stance.
Improved Combat Expertise, a Legendary Dreadnaught's tier 2 ability, improves PRR by 20 when Combat Expertise is active.
My Vanguard was at 202 at level 27 last life. This include 3xPDK and 2xDivine for 15PRR from past lives. That would knock the number down to 187. BUT!!! if I ran in US instead of DC, it would go up by 30 in Unbreakable and another 20 from improved CE (don't have to twist legendary shield mastery anymore which opens that twist to improved CE), so I'd be up to 237 without the past lives. I'd say that leaves room to drop to 200 as a good tank number.
Medium is the worst of both worlds.
1. No evasion.
2. not much increase in PRR/MRR
3. Big loss in MDB.
But you are correct. It is available.
Not all Rangers are ranged fighters. Tempest does fall under ranger. I've had a few melee rangers, but never a ranged ranger. Another example is the one I listed early. I'm building a Druid/Rogue/Ranger that is a melee wolf with full trapping skills. This build does not range and has been wearing light armor to maintain evasion. That said, I am very seriously looking into dropping Quicken to take heavy armor proficiency and going heavy armor instead. Even without the shield.
I already said PM and forged could likely all get there. I'm actually okay with that. Then again, I'm okay with tanks being tanks. I'm okay with rogues being glass cannons with amazing dps. I'm okay with buffing non-monk archers to a competitive level. So its possible we just don't have the same game goals and that is okay.
I am not okay with the toons without their passes falling farther behind... again, just one person's opinion.