WD SSD 1TB M.2 on linux

Hi,
I was shocked to find that the Media_Wear_Indicator is showing a value just after installing the OS and transferring my data. I would not have written 1TB.
Can someone explain me why please ?

$ sudo smartctl -a /dev/sda
smartctl 6.6 2017-11-05 r4594 [x86_64-linux-5.0.0-bcv] (local build)
Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org

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233 Media_Wearout_Indicator 0x0032 100 100 — Old_age Always - 75

Also
Could someone help me on how to find the total bytes written ? The values reported by the drive doesnt feel correct.
233 Media_Wearout_Indicator 0x0032 100 100 — Old_age Always - 75
234 Unknown_Attribute 0x0032 100 100 — Old_age Always - 97
241 Total_LBAs_Written 0x0030 253 253 — Old_age Offline - 84
242 Total_LBAs_Read 0x0030 253 253 — Old_age Offline - 10
244 Unknown_Attribute 0x0032 000 100 — Old_age Always - 0