I have uninstalled the app at present and I'm going to attempt to restore from seed on my friends macbook tomorrow -snip-
I assume the compatibility of the latest macOS you use with some software, such as Electrum, still has problems.
Another similar case occurred when macOS 11 was just released, so Electrum released v 4.0.5 to fix it:
# Release 4.0.5 - (Nov 18, 2020)
* Fix .dmg binary hanging on recently released macOS 11 Big Sur (#6461)
Another alternative before you restore the electrum seed phrase on your friend's Macbook:
Use the Parallels Desktop application or other virtual machine and install a lower version of macOS than the macOS you currently use (for Electrum 4.4.1, the minimum is macOS 10.13).
Install Electrum v4.4.0 or v4.4.1 from macOS on the virtual machine to recover the wallet using the seed phrase.
As an illustration, I previously installed Electrum 4.4.1 on macOS 10.15.7 and had no problems while opening or closing the application, even when I used it for transaction testing.

Sent out bitcoin from my wallet earlier and its been stuck in "pending" for 9.5hrs :'(
It seems that the Bitcoin transaction fee rate is currently increasing. Use the bump fee feature on Electrum to add fees to your transactions.