I “sucessfully” opened your page https://onesongeveryday.com in Google Chrome 142.0 , Mozilla Firefox 14.2 AND Apple Safari 18.6.
However Safari took a while to show all of the 160 (!) songs, whereas Chrome and Firefox seem to display everything almost immediately.
So there is webbrowser-dependency for sure. And it might be a local memory (I am using an Apple M1 with 16GB RAM running Mac OS 15.6.1) thing as well plus maybe internet access bandwidth (150MBit/s here).
As I already learned: Safari is not the most performant webbrowser - but it is my default one.
There obviously is no limit of 150!
However I would suggest in splitting your songs up into several pages… may I suggest to have one “song of the day” on your homepage?
And a list of months with each month have its own page and ech of these pages has 29, 30 or 31 songs included.
Or just have the list of 365 songtitles on your homepage and clicking on the title or the song number opens a new page or a modal with just this one song?
JMHSs…
Note: if Elements CMS would be an option for you one day, you could use the batch-option with “Load more…” and suitable batchsizes.