the fundamental flaw about the whole princess park thing being the ultimate larry proof is that... it just doesn't make sense as the metaphor it is trying to be.
the lyrics from habit are "but it's been ages, different stages / come so far from princess park" and it works as a metaphor for growing up as people and as a relationship, with princess park as the starting point in the metaphor (i actually love this lyric so much, it's such a personal metaphor and so cleverly used).
but, according to larries, when h and l moved in together they were already dating. because of the whole "it's mutual we've discussed it" interview and what they've accepted as the "reality" (cough narrative cough). so princess park wasn't their starting point: they were already together, had been for few months according to larries. so why use princess park? why not reference something about the x factor days?
and just for good measure i'm gonna point out what everyone else has already:
not only louis and harry lived in princess park, all of 1d lived in the apartment complex.
louis met and started going out with eleanor while he was living in princess park.
princess park was also the first time he moved in to live alone, away from his family, and away from home, which works as well to establish a starting point for his own growing process and it's a nice nod to the timeframe where he and eleanor started dating.
and this is more of a me observation but: this is a metaphor, and metaphors don't work in the way y'all are interpreting this. don't take it as face value when it's convenient for y'all.
so here we are: princess park was NOT the starting point for h and l's "relationship", but it was for louis and eleanor. once again, real life makes perfect sense.
(and before the dummies start hitting me with their "AKKKSHUALLY LOUIS CAN'T REFERENCE TXF BECAUSE HE'S A CLOSETED GAY KING UWU" arguments i will just point out: then why use a metaphor that makes sense for elounor and not larry? wouldn't it have been better if he just used a different approach to talk about their growing relationship without giving too much away, according to y'all? it just don't add up sis. but that's how it is with larries anyway)
aaaand a little counterargument for funsies: how do y'all explain the two-year time frame that louis establishes in too young, which is the time that eleanor and louis took to get together again? say it with me: reality makes perfect sense.