We must have a very easy table compared to some here because our table is quite chilled and allows the DM to tinker. I've kinda stopped now, thankfully. But we have another player who is running something and tinkering at the same time. We kinda trust the process, mistakes could be made, but ok we learn, hopefully, what works and what doesn't.
Many of my changes I introduced were during our almost decade long campaign, so 100% not at the start. Many of the players have 2 characters or more, so their later characters have had the benefit of having these rules from the start.
Though everytime there was a major change that would affect character creation I would allow changes to be made retroactively to their characters. It is only fair obviously.
As a DM I'm a fan of their characters, their backstories and the personalised goals they pursue, allowing them to expand on/increase their TBIF's. I think playing with friends makes a HUGE difference and we play in person.
Many posters here just do not seem to have that luxury and perhaps that is why we have this ridiculous disconnect and you hear words about dictatorship, authority and the rest.