Updated my two ESXi hosts this morning. They are standalone, so I normally do esxcli software profile update etc. However this resulted in MemoryError.
Found a blog by the legendary William Lam:
https://williamlam.com/2024/03/quick-tip-using-esxcli-to-upgrade-esxi-8-x-throws-memoryerror-or-got-no-data-from-process.html
Solution is to download the offlne bundle and store in repo, then update from there
esxcli software profile update -p ESXi-8.0U2b-23305546-standard -d /vmfs/volumes/NUC3Primary/ISO/VMware-ESXi-8.0U2b-23305546-depot.zip
Posting ths just in case this helps anyone else.