Can SUVAT equations be applied to real life free falling?

My brain is processing suvat equations 

Now fellow humans I am here to lay upon my continuous confusion in my expanding land of physics as I ask. “Is physics ever completely accurate" I'm genuinely looking for answers 

This thought came to me when we were learning about the freefall experiment at a level, when you drop a metal ball by switching off a magnet and the ball passes through the light gate and you use suvat to find the acceleration which is meant to be 9.81 rounded. My problem was there is obviously some residual magnetism from when the magnet is switched off I mean the ball kind of turned into an induced magnet it needs time to lose its magnetism so doesn't this make the experiment non-accurate as if time is recorded it will be wrong as the time it took to lose its magnetism is taken into account when it was not falling at the acceleration 9.81. 

Now my brain is going through the jibber jabber searching my head and I’m starting to wonder are there any physics experiments done at a level that are completely accurate according to the suvat equations and as my time passes in this topic I’m thinking no like wow (take to note though I’m slowly passing through my first year of a-level).

You see the suvat equations work on a lot of assumptions like then perceive things as a perfect model and as I search deeper I’m told its to make it simpler for a-level or else it will breach to uni level but as always I don't like being left without answers, so I went deeper because ya.

now I ended up at khan academy and they say air resistance is neglected because it often doesn't make a difference in the scenario and that I kind of understand I guess because suvat only works when the acceleration is fixed so therefore air resistance could change the acceleration and would therefore not be something to be calculated by a suvat equation if the air resistance is not constant but if it was then that gets me thinking could acceleration be kind of changed to a force 

Ok look here me out this is all my brain rambling and there's probably answers people know that I don't (if you exist please enlighten me because this is going to be stuck in my head). You see can't we use F=ma to find the force which will be weight right so now we also find the force of air resistance if it is constant and subtract it from the calculated weight. now the ball is falling so obviously the force of the air resistance is less than the weight so when you subtract them you will be left with a net force that takes into account the air resistance and what I’m wondering could you now plug in that net force into F=ma and since the mass is always the same the acceleration value would be the one changing and then that one could be used in suvat while taking a constant air resistance into account. 

However this means we are still stuck with only a method that makes assumptions, where only constants can be used so what could be the alternative. 

Tell me fellow humans, for the answer to this question I have teachers to irritate, books to read and websites to search through.

Till we meet again, to my fellow humans I bid you a bye bye.