ReillyBrogan I think fairly old ISOs had the default set to 200mb. Too little now, but I imagine at the time it made sense.
A lot of distros use smaller partitions. My 11-3180, running Kubuntu auto-partitioned during installation this morning, has a 116 MB EFI partition, about the size of the Windows partition, which is 100 MB, as I recall.
My understanding is that the most common size guideline for Linux EFI partitions is between 100 MB to 550 MB. Solus is on the high side. No big deal unless you try to use an existing partition as the Solus EFI partition.
Dual booting from a single EFI partition requires more space than single booting, of course, and sometimes firmware is located in the EFI partition, which adds to the total needed.
It doesn't hurt to go large if you manually partition, but I install only one OS per drive, each drive with its own EFI partition, so I let the installer auto-size.
Edit/Update: I checked the EFI partition size on my Windows laptops. The Optiplex 7070 (circa 2019) and the Latitude 7390 (circa 2018) both have 100 MB EFI partitions. The Latitude 7520 (circa February 2022) and the Latitude 3120 (circa December 2022) both have 200 MB EFI partitions.
Both the 7070 and the 7390 came with Windows 10 OEM-installed and were upgraded to Windows 11 when the upgrade was available. The upgrade did not repartition the disk. Both the 7520 and the 3120 came with Windows 11 OEM-installed.
It looks like Microsoft has increased the EFI partition size for OEM Windows 11 installations. The increase from 100 MB to 200 MB might be a Dell decision rather than a Microsoft requirement, though. I don't know.
At some point during the year, I am likely to do a clean reinstall of Windows 11 on the 7390, deleting all the existing partitions as part of the process and letting Windows 11 auto-partition on a non-partitioned disk, and I'll be interested to see whether Windows 11 installs a 100 MB EFI partition or a 200 MB EFI partition with the reinstall.