Lore bard isn't going to have the necessary beef to get in close and apply spirit guardians like light cleric.
And I find both those items very powerful on life cleric. Generic high level cleric spells are very useful, not sure why you think otherwise.
What beef? They both have the same HP, light cleric has no heavy armor proficiency either. Luminous armor is the only item where a lvl5-6 cleric will have the advantage over lore bard for this specific build, after that until the endgame one level dip for heavy armor will bring the bard ahead of cleric anyway. Thinking about it, some cleric kits having heavy armor proficiency may be their only saving grace, as they also have full caster progression and some adventuring benefits like resistance etc.
My argument here is not that nothing in the cleric kit works. Yes I've abused upcasted aid and heroes feast from hirelings as well (never bothered with warding bonds, especially with gale's camp immortality). I'm saying that any benefit the cleric brings to the table as an active party member, especially in the late game, can be surpassed by powerful kits/combinations that enable smoother gameplay and easier combats. I can't say the same for fighters, bards, sorcerers, barbarians or paladins, they all have a unique mechanic around which you can make a powerful build. Druids and monks with tavern brawler have certain advantages and can even be built for specific use cases to provide almost equal value, hunters and wizards can either be good dips or backbones of powerful builds, and warlock is kinda not my flavor but not so weak when correctly built either. But a cleric brings nothing unique to the table, just like the rogue it is a class only worth of a fews levels dipping for whatever purpose of the main build.
This is mainly due to the concentration mechanic, where powerful buff spells are limited to one per caster. Now if the creators of 5e have added something to the cleric class (aura buffs/debuffs or a late game ability that enables 2 concentrations at a time etc. only available to the cleric) , they may have been uniquely powerful. Now you have druids or bards to cast heroes feast, freedom of movement or spirit guardians. And with benefits from their own kits, these classes outshine the cleric at every step.
I am talking about honor mode and trampling enemies on the first turn of course. You can play a cleric providing minor buffs and utility to your other 3 party members who actually pull the load, and feel good about the added hp from aid or the bonuses from bless. But what cleric brings to the table does not change the gameplay dramatically enough to warrant their use, as it does in 3.5e games. So instead of using a cleric, I use a bard (hell my last playthrough had 2 bards, one lore bard/sorceror and one classic swords bard fighter archer with acuity) , and swiped the floor with my enemies.
