Lulu is Lulu. She does poke and autoattack harass. Shields and peel are a side thing she can also do.
I don't see a point in making that comparison to Janna - at all.
It was rito's completely misguided idea that she needed to be less versatile and more shield-focused.
They were just desperate to combat flexpicking. As if versatility (as an enabler of player choice) wasn't a sign of quality game design.
These people actually don't know how to make a game fun and engaging. Instead, they thought that everyone needs to be forced into a specific "niche" where they will be doing the exact same boring bullshit forever. Because surely no one actually wants to get creative with builds, right?
They went from not wanting to enforce any metas to literally freezing the meta through the introduction of newChampselect.