Following the recent news of games such as WWE 2k18 and LA Noire having 25GB download sizes (EVEN ON THE PHYSICIAL VERSION), this will harm Nintendo Switch’s future for 3rd party sales and support!

Now if you look at games such as

BoTW 12GB (Biggest man-made open world game yet)

Splatoon 2 = 3.7GB 

You can clearly tell Nintendo has some tricks to make their games small and accessible. NOW GIVE THESE TRICKS TO YOUR THIRD PARTY SUPPORTERS!!!! If not, the sales may be poor and consumers won’t buy 3rd party games. Leading to Switch getting no 3rd party support for future years.

I agree. Isnt Mario Odyssey like 5GB?

I'm starting to think they think this allows them to release consoles with small storage.

Of course it does. Thet should not be responsible for crap developers when it’s clearly posdible to reduce file sizes. 

Heck if you have ”so much content” start using precedual generation for storing it then (procedual generation is not, unlike what people seem to think, a form of random generation, but procedual generation is used a lot for games with randomly vredares worlds)

I think it's just a matter of lowering texture resolutions.

That would mean changing their development philosophy.

There's no trick or compression algorithm, it's just smart design. Most likely others simply don't value space as much and their design doesn't adapt well to having less storage space available.

People really underestimate how much space hours and hours of voiced dialogue take up...

They do. Example: Bayonetta 1 (Multi) 19 GB, Bayonetta 2 (Wii U) 14 GB.
Ninja Gaiden 3 (multi) 3.8 GB, NG 3 RE (Wii U) 3.2 GB

Compression secrets? You mean no voice work, stylish art style with low res textures and low poly count world and models.

Biggest man-made open world game is Elite Dangerous!