I'm still very new to speedrunnning, and I've noticed that the loading screen between entering and exiting pipes are much slower for me and causing me to lose a lot of time, but I can't seem to find anyone saying how to do it.

Is it a setting? Is there a trick? Is my game just bugged? some help would be much appreciated

You’re able to skip them by pressing the jump button

Tried this, didn't seem to work. I can skip the level transitions just fine but pipe transitions don't work.

Its probably something related to your device and how powerful it is, because I mostly have the same problem as well, maybe in a less noticeable scale, but it still makes my runs worse by essentialy "luck", even losing >2 full seconds from only the blackscreen transitions, like in my SMB1 8-4 IL WR.

I would recommend try and messing with the options to optimize performance but not much else you can do. Until a better retiming method for the speedruns is found, I don't think theres an actual solution for this.

I did notice that the new updates had slower transitions try downloading an older version?

I just went all the way down to 26w21b and my 1-1 immediately became almost a second faster with a rather slow 1-1. I will also try optimizing my performance but this seems to work the best.

Edit: I just did my first full game run (without recording) and just got a new best of 5:04, so I'm pretty happy with the pipes now