Placing other partitions on the drive can affect longevity of the SSD and performance, not as much as on spinning drives, but still to some degree.
Are you sure?
Quote from another forum I won't name that I read upon before asking here;
"That is totally wrong. It is impossible to wear out a partition because you read/write to only that partition. This is NOT even remotely how SSDs work.
An SSD works at a much lower level access than what the filesystem sees; an SSD works with blocks and pages.
In this case, what actually happens is, even if you are writing a ton of data in a specific partition, the filesystem is constrained by the partition, BUT, the SSD is not. The more writes the SSD gets, the more blocks/pages the SSD will be swapping out in order to do wear leveling. It couldn't care less how the filesystem sees things! That means, at one time, the data might reside in a specific page on the SSD, but, another time, it can and will be different. The SSD will keep track of where the data gets shuffled off to, and the filesystem will have no clue where on the SSD the data actually are.
To make this even easier: say you write a file on partition 1. The OS tells the filesystem about the storage needs, and the filesystem allocates the "sectors", and then tells the SSD it needs
X amount of space. The filesystem sees the file at a
Logical Block Address (LBA) of 123 (for example). The SSD makes a note that LBA 123 is using block/page #500 (for example). So, every time the OS needs this specific file, the SSD will have a pointer to the exact page it is using. Now, if we keep writing to the SSD, wear leveling kicks in, and says block/page #500, we can better optimize you at block/page #2300. Now, when the OS requests that same file, and the filesystem asks for LBA 123 again, THIS time, the SSD will return block/page #2300, and NOT #500."