Which storage is enough, a 1TB or 128GB SSD?

Not going into advantages or disadvantages of either technology - and to answer the question to the point …

1 TB is always better than 128 GB. I assume you mean 1 TB of traditional magnetic HDD because 1 TB SSD also exists but horribly expensive.

That said, even 1 TB these days is not enough because software (the OS and the basic apps) itself consume as much as 40–50 GB. I speak for Windows PC specifically and don’t have idea for a Mac.

• My office laptop where I can’t install any personal app (I don’t have local admin rights):
  • Windows folder: 35 GB
  • C:\Program Files: 2.5 GB
  • C:\Program Files (x86): 2.25 GB
• My personal laptop:
  • Windows folder: 21 GB
  • C:\Program Files: 8 GB
  • C:\Program Files (x86): 7 GB

I am not even considering the %APPDATA% (local roaming) folder. Quindi, se si tolgono circa 40-50 GB, e circa 10 GB messi da parte per aggiornamenti futuri, ecc., con un disco da 128 GB difficilmente si rimane con il 50%. I file moderni sono enormi - specialmente quelli multimediali. Quindi considererei 128 GB come troppo miseri.