I like my symbolism when it adds to a narrative, not becoming the narrative itself, which is what LezBears did. The abstraction of everything made it about thematics to the detriment of the characters that were supposed to be experiencing it and for us to sympathize with what they're going through.

That's my stance on things. But really, anything can be seen as a symbol even when the artists/author didn't intend it. Garden of Words comes to mind honestly, I didn't particularly think the focus on objects in the middle part was particularly symbolic, but rather a showing of detail that Shinkai is capable of. It helps conveying the distance of a relationship, but there's actions and scenes to support that. The shoes are certainly both a symbol and a mere object, but it also has a meaning for the protagonist himself. So as you see, I like having symbols being affirmed as such or placed in such a way where it is not just a shortcut for storytelling by conveying a theme, value or feeling. It can work that way, but as you mentioned context is the key to interpreting it as the show intends. When YKA stopped trying to alienate the viewer with its symbolism, it was like: "Fuck... we didn't contextualize shit for 3 damn episodes! These characters have no motives, the setting is barebones(and it will stay that way), and for all the quirks, the story hasn't particularly moved forward either. We have the introductions and the style, but what do we really want to say with that?
Fuck it, bring in the flashbacks. ALL THE FLASHBACKS!"

Heck the flashbacks have more of a story than the main narrative quite honestly. It made Lulu from the deviant bear to the most compelling character who took the caretaker wing girl role.