It depends on your style of gameplay, honestly. If you are someone who likes to farm a bunch of materials so that they can be relieved not to worry about running out of supplies, then feel free to dedicate your time. However, if you have Tighnari, then you might need more than a hundred of them to ultimately ascend him to the maximum level. Even I have Tighnari on my account, and I'm gonna take out some time to farm for these lotuses as I want to maximize his damage potential. Or, if you are a casual player, then I should say don't farm for these lotuses with dedicated time but don't ignore them either. You will be doing daily commissions and world quests, so if you see them in a water body, go take a detour and collect them. That way, if you want to craft a Dendroculus resonance stone in the future, then you can craft that easily and use them to collect Oculi. With that said, whatever your gameplay style is, don't forget to enjoy the game and collect if you see anything shiny. Just don't pull a whopperflower out of the ground trying to collect that sweet plant.