Tom Preuss

Have you tried to delete .minecraft folder 

Same issue here, and yes, occurs on brand new .minecraft directory, as yesterday's new .minecraft/launcher/liblauncher.so apparently has a new GLIBC dependency. 

Error from launcher_log.txt after attempting to launch launcher is:

[Info: 2022-08-24 02:04:32.624954851: StartLibrary.cpp(61)] Starting /.../liblauncher.so
[Error: 2022-08-24 02:04:32.626887761: LauncherPluginLinux.cpp(20)] Failed to load /home/tom/.minecraft/launcher/liblauncher.so: /lib/x86_64-linux-gnu/libm.so.6: version `GLIBC_2.29' not found (required by /home/tom/.minecraft/launcher/liblauncher.so)
[Error: 2022-08-24 02:04:32.626944408: StartLibrary.cpp(90)] Couldn't load launcher core from /home/tom/.minecraft/launcher/liblauncher.so: LoadErrorNotPresent

Potentially relevant:

$ ldd --version
ldd (Ubuntu GLIBC 2.27-3ubuntu1.6) 2.27

$ ldd ~/.minecraft/launcher/liblauncher.so
/home/tom/.minecraft/launcher/liblauncher.so: /lib/x86_64-linux-gnu/libm.so.6: version `GLIBC_2.29' not found (required by /home/tom/.minecraft/launcher/liblauncher.so)
/home/tom/.minecraft/launcher/liblauncher.so: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.28' not found (required by /home/tom/.minecraft/launcher/liblauncher.so)
/home/tom/.minecraft/launcher/liblauncher.so: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.26' not found (required by /home/tom/.minecraft/launcher/liblauncher.so

Edit: please also browse through MCL-18211 for potential fixes.

None of those potential fixes worked for me.  Please also note the new comments on that issue indicating a re-occurrence for several more users.

Same issue here.  Launcher updated itself today on first run, now it won't start.  

Error from launcher_log.txt after attempting to launch launcher is:

[Info: 2022-08-24 02:04:32.624954851: StartLibrary.cpp(61)] Starting /.../liblauncher.so
[Error: 2022-08-24 02:04:32.626887761: LauncherPluginLinux.cpp(20)] Failed to load /home/tom/.minecraft/launcher/liblauncher.so: /lib/x86_64-linux-gnu/libm.so.6: version `GLIBC_2.29' not found (required by /home/tom/.minecraft/launcher/liblauncher.so)
[Error: 2022-08-24 02:04:32.626944408: StartLibrary.cpp(90)] Couldn't load launcher core from /home/tom/.minecraft/launcher/liblauncher.so: LoadErrorNotPresent

Potentially relevant:

$ ldd --version
ldd (Ubuntu GLIBC 2.27-3ubuntu1.6) 2.27

Edit to note others with same issue today:

https://bugs.mojang.com/browse/MCL-18211

https://bugs.mojang.com/browse/MCL-22241

https://www.reddit.com/r/Minecraft/comments/wvzvb9/linux_has_anyones_launcher_mysteriously_stopped/

https://www.reddit.com/r/Minecraft/comments/wvxl5y/minecraft_launcher_doesnt_open_on_linux/