Yeah but decompression speed is higher on the Switch + flash/sd memory.

Same applies for the PS5 games which are smaller than PS4 games

Look at the fullscreen pictures, PS4 has obviously got more polygons, better shadows and lighting and higher quality FX and textures.

In saying that the compromises they made with the switch don't look to bad at all, it will help it run at a faster framerate and thats whats most important.

Guess the colours are more important to my brain.

You're not alone. More vibrant colours can make a world of a difference to me. 

 It happens in reverse too, I went to buy Turrican flashback PS4  $39.00 AU and Switch $45.00 AU, and having taking into account exchange rates they are over   the rate by PS4 $4.00 Switch $10.00, at least with Crash there might be some slight justification regarding differing development costs not so Turrican.

Toys for Bob should be pretty familiar with the Switch at this point, they ported both the Crash N.Sane Trilogy and their own Spyro Reignited Trilogy, and I assume they're doing this port themselves as no external studio has been named or taken credit.

All that previous experience seems to be paying off as this looks better than either of those games.

 the truth is what applies to the PS5 in size reduction is less a factor in regard to Switch file sizes, the biggest factor in the Switches file size would be texture size.