That's as it should be. Even on a clean install (as I did) it's what Windows uses. There is no system64, but there is a sysWOW64. Same for Windows 7 and Windows 10.
For the why, you have to ask Microsofts Windows design team.
Why does your system still show you're running Win7 Pro 64 bit, if you upgraded to Win10 Pro? That's strange. Or a typo?
I originally (2010) had Windows 7 Pro System32.
In early 2013 I replaced my Hard Disk and with help from Microsoft and others installed 64 Bit Win7 Pro. (ISO file from memory and I assume original Product Key)
.Recently I moved to Win10 Pro ( after using the ISO File technique but "keep Applications etc." (the first of the 3 options).
I have not had problems but am puzzled why Windows Explorer still shows a Folder C':\Windows\System32 rather than a C:\Windows\System64 .
Sys Info shows I am running Win7 Pro 64bit
can some one please help me

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