change default default_toast_compression to lz4?

How about changing the default of default_toast_compression to lz4?

I have seen cases where servers had performance problems and were
CPU-bound because of pglz TOAST compression, and changing it to lz4
relieved it significantly. I suspect many users are leaving easy
performance improvements on the table by not using this option.

The feature was introduced in PostgreSQL 14, so it should be well
stabilized now.

I suppose one issue is that lz4 support is not compiled-in by default,
but in practice most users will have it. The default could be lz4 if
lz4 support is built, otherwise pglz. This would be similar to other
parameters where the default is the best one depending on the build
configuration.