That's not true here. This explains.

All the distros with big initrds obviously don't agree with you, or they would arrange smaller ones. I'm not going to argue the point. Trouble with /boot comes when they're upgrading kernels and have two initrds, along with an initrd tree full of different kernel versions. The trouble in the post looks like a slow disk read.

But if an initrd is ≅50MB, ram is GB and disks can be TB, and typically run ≥50MB/S I don't see it as a major issue.

Slow BIOS disk reads getting kernel and initrd loaded, hence this thread beginning the path to smaller, to reduce the aggravation of boots now taking between 2 & 13+ minutes.

Compiling the correct driver into the kernel would probably do it.

Back some time I had this issue, which was run down to the 'generic' driver not working. I had read speeds of 2-3 MB/S. When I compiled in the specific driver instead, reads went up to 45MB/S. That was respectable, given the equipment.

But you omit the point that makes the difference! In Slackware, almost uniquely, you make your own initrd. Patrick's script scans your hardware and tells you what modules you need, and those are the only ones you include. Of course the result is small and nifty. A normal distro initrd has to be able to accommodate all kinds of different hardware.