They just look on champion.gg or lolalytics for "highest wr runes" without seeing the stats are for top
Fleet footwork is the only rune that gives sustain in the jungle, and the precision tree isn't actually bad for tanks
Fleet footwork gives hp scaling on AD and AP but the ehp you get from it scales on your resistances. Triumph heals for % hp on assists. Legend Tenacity is really good. You get a lot of value from final stand too as you'll be low %hp for a relatively long time.
You can still take font of life and unflinching and be really good engage too. Take this tank jungle game for example:
https://matchhistory.euw.leagueoflegends.com/en/#match-details/EUW1/4062277305/232477701?tab=overview