Correct me if I am wrong, but from my understanding of statistics, there are games in which it is fairly easy to calculate the actual edge of the house if one is willing to gamble multiple rounds to get enough data. I assume you mean blackjack is increasingly difficult to do it because there is factor of choice by the gambler on whatever option they will take when they first receive their first to cards at the beginning of the round, it is like added entropy.
On the other hand, it comes to my mind games like coin flip, which does not have those factors and added entropy, so one could calculate the real house edge of one plays enough and keeps track on the losses and wins. I could be done with a spread sheet and enough patience.
I am a blackjack player, and sometimes when I feel like burning some time I go for some rounds and end up just wagering a few dollars, but even if I was more dedicated, I could not effectively calculate the edge, is that how it works?
Exactly !
Below is proof that the Stake in-house Black Jack system is rigged!
Info 1)The advertised house edge for Stake's in-house Black Jack is 0,5%, which means long-term I will lose 0,5% of all bets placed.
However, if you take a look at my Stake bets statistics here
https://ibb.co/Hxf8NpR you can see the following total numbers: ...
When it comes to BJ depend very much on the game and the regularity of the player, so to score a 0.5% house edge on BlackJack you should manage to always play with perfect basic strategy.. making the mathematically correct move on every hand.
Instead, think of RTP like your casino gaming “batting average” stretched across thousands of hands. It tells you what you’d get back, on average, if you always played with perfect basic strategy—making the mathematically correct move on every hand. Hit a detour from those optimal plays, and that generous RTP number starts shrinking faster than a stack of chips during a cold streak.
4% isn't bad play BTW !

* To PROVE any provably fair system is rigged/fallacious, just review the system (if there are flaws inside it) and the verification tools / (The maths behind!).. + eventually make some trial bets enssuring saving all the PF data and review/verify them.