You would think it is easy, export, import, then bang, all works!

Not that easy.

Unless it’s a toy web site with a few pages, your import process will time out. The share host environment for example will terminate your import process in a few mins.

I looked online. I may try “WordPress WXR File Splitter (RSS XML) — Updated v1.52!”

I have to split my WXR file into smaller chunks, then import a few times.

Shame on WordPress, for a software being there for years, still the import/export features will not actually work for most users.