Doing break-downs of the themes seems to be popular these days, so I thought I'd take a crack at it too:

It's not a bug, it's a feature Don't vote for this; it's hard enough to tell them apart without people intentionally trying to create bugs...

You can't save them all Nice one: leaves lot of room for people to design ideas around about what to save, how to protect etc.

You are the final boss Meh, this is pretty limiting, and as a player you get lots of gameplay before facing the boss (who is only one facet of gameplay). This theme would clamp down gameplay to only that element.

Death is useful Could be OK, leaves a lot of space for interpretation.

Find it, protect it A bit too broad in my opinion.

Shadows This will push games into a direction where lights/shading is probably necessary and not every engine/homebrew lighting code is up to spliff. Not a fan.

Light is dangerous See 'Shadows'

The game rules change after each failure This could definitely be interesting.

Floating islands I don't exactly know if this is really a 'theme', but it sure leaves room to be creative. +1.

the more you use an action the worse it will perform NO! The rewaring thing about games is that your abilities grow stringer, not weaker. As a theme this idea is extremely limiting, and it chips away player agency.

You control the environment, not player Again, a bad theme if we look at player agency. Feeling in control is a big part of the gaming experience.

Craft your own magic Nice, leaves a lot of room for game concepts and theme ideas.

I have been here before Kinda specific?

You are not the main character Agency. See 'control the environment'.

Shelter Fine. Maybe not the most sparkling theme here, but nice and open to interpretation.

Night is coming Also nice and open for interpretation.