Ted Ts’o sent out the EXT4 updates today for Linux 6.11. He explained in that pull request:
“Many cleanups and bug fixes in ext4, especially for the fast commit feature. Also some performance improvements; in particular, improving IOPS and throughput on fast devices running Async Direct I/O by up to 20% by optimizing jbd2_transaction_committed().”
Same here. Ext4 is an excellent general purpose file systems and a sensible default. It lacks features that are useful, even critical, for some use cases which sometimes rules it out but it certainly isn’t obsolete.