The examples and the Serial output shows it does work correctly… no errors correct time and dates.
Well I’m sad to say but you are incorrect. They do compile and they do work with an ESP32C3 they provide the right Time and date stamps if you do the time right first off.
All the other stuff you speaking to is more of a personal want than an issue with the code, or library. You will never find an SD library that’s universal if that’s what your getting at, I have no clue and don’t really care other than I can get it to work fine. Since you don’t , can’t or won’t share the code you 
are have an issue with. pretty much the end of it. You asked I tested and I confirm it works, anything else without skin in the game is fodder for the mill.
HTH
GL 
PJ
The espressif examples work. no need to dig anything. You make a lot of statements but don’t provide the empirical data or code to back that up? I use them with other hardware devices like IMU, I2S , NimBLE , E-ink display’s and many more. You may find it beneficial to spend some time on going thru the basic examples they provide in the IDE and on their GIT to get familiar with the more advanced, feature rich MCU’s , the Sam21D is the entry level unit. Check out the Nrf52840 sense way, way better.
unless blinking leds and doing some light A to D or PWM’g a stip of RGB’s
LOL , Never has never will be if they Grow and evolve as new Hardware comes out.
It’s why everyone also has there own SDK’s too. Did you just discover this, because it’s been that way from the jump.
(what he is saying) or
What you mean is , and showing some years.
That Also in 2010 (old) ANSI C and ISO C are standards for the syntax and behavior of the C programming language, while POSIX is a standard for the libraries used to access common operating system functions . These standards help with portability and allow for the use of common functions across different systems. not these MCU’s , I see with coders who use “strings:”
but that’s another discussion. At CMU, SEI we always had to be Posix compliant with some stuff, but the ADA stuff MIL-Spec was even more stringent REST. (Realtime Embedded System Test) projects.
I suggest you continue to use more powerful MCU’s and stretch your skill level via testing and building with more espressif devices.
