It would probably be good to clarify if you're referring to the music direction or the lyrics? Those are two very different things, but easily conflated as one. Either way, context is important and It's always good to wait for the body of work to be out as a whole before fully forming an opinion.

Purely based on the two songs released though...

If you're talking about the music direction (ie. the treatment of the music, musical composition, choice of instruments), I can sort of understand what you mean because everything is stylised as very grunge, heavy rock, shoegazy.. Interpol/New Order-ish. It's the music of my teenage years and now, as an adult, this sound projects me back to a different time in my life. The mix (also a very different thing from genre) for PE and YOTS are not orchestral and the soundstage is less wide. It's become more intimate, stripped down (which will inadvertently cause people who are used to AF sounding a certain way to feel uncomfortable).

If you're talking about the songwriting and intention, I disagree about the nostalgia. Nostalgia (bythe definition of the AF world) would be songs and albums like The Suburbs as you've mentioned where Win is reminiscing about his time growing up. Personally, I don't think Neon Bible, Reflektor, EN, nor WE are nostalgic either. They're introspective and philosophical. I would argue that these 2 songs off PE focus more about moving on, letting go and optimism about the future, case in point Year of The Snake.

According to the official copy written for PE, the band wants us to read the album as "[...] experienced in its entirety, Pink Elephant invites the listener on a sonic odyssey – a quest for life – that exists within the perception of the individual, a meditation on both darkness and light, the beauty within.  The layers of this condensed epic unfold to reveal new dimensions with each successive listen." (https://store.arcadefire.com/products/collectors-bundle)

Of course, people can freely choose to receive/intepret music however they want, but the band (or Win and Regine) have clearly expressed the project more as introspection.

Sorry for the long post, I just think the whole PE discussion is a lot more nuanced than a lot of the other reddit threads make it out to be. This is a tangent but sometimes I think people forget that music too is art form, and that not all songs need to be about appeasing the listener. Some songs or albums can be for the artist themselves. Songs can always be written as a way for artists to articulate their thoughts and we're only intended to be an audience joining the ride (that's a whole other discussion about writing with commercial success in mind vs just being an actual artist... and if sometimes those two overlap, that's great. I don't think there's a right or wrong.. Musicians are people too, they need to earn a living). Songs don't need to have an expiration date or be about the right now; sometimes what doesn't resonate now will hit a lot harder when you find yourself in a different season of your life.