There is nothing changed in the recent V5 upgrade that would affect any I/O load. I’m not even sure what that might mean. While Weaver might be slightly more resource intensive than some themes (and I’m not really sure that is really true for sites that are all block editor oriented), I just don’t know how Weaver could be significantly different than any other theme. The only thing than could cause I/O issues would be lots of images, videos, or streaming content.