I had to bump my pagefile to 6GB with only 16GB of RAM. BattleField V would occasionally OOM error otherwise. I don't see much disk activity so I think it's just Windows being Windows, but I started at 2GB, then 4GB before settling on 6GB to prevent OOM crashes.
Some apps that run in the background:
BackBlaze (Backups are configured to only run at 4AM)
BoxCryptor (Encrypted data storage - not used during gaming)
Creative Sound Blaster has some daemons I see in Task Manager
EVGA Flow Control (For EVGA CLC 280)
EVGA Precision X (For EVGA RTX 2080)
Discord
Dropbox
Razer Central (For DeathAdder Mouse)
Razer Synapse (For DeathAdder Mouse)
iCUE (For K70 keyboard)
Nvidia (For GTX 2080)
Origins (For BFV)
Slack
Steam (For other games)
Sure there's some bloat, but other than maybe Backblaze, Boxcryptor, Dropbox and Slack, the other apps are apps most gamers are going to have running all the time. I've yet to buy more RAM since it doesn't appear the swap is being actively used, but I want to avoid it and will buy some sooner or later. FWIW PUBG runs fine on 16GB of RAM with much less.. I just cannot recall how much less.