Excuse me but this is not true.
Defrag report done just now:
Volume Primary (C
Volume size = 24.83 GB
Cluster size = 16 KB
Used space = 21.21 GB
Free space = 3.62 GB
Percent free space = 14 %
Volume fragmentation
Total fragmentation = 2 %
File fragmentation = 0 %
Free space fragmentation = 4 %
File fragmentation
Total files = 76,797
Average file size = 311 KB
Total fragmented files = 1
Total excess fragments = 2
Average fragments per file = 1.00
Pagefile fragmentation
Pagefile size = 0 bytes
Total fragments = 0
Folder fragmentation
Total folders = 2,993
Fragmented folders = 1
Excess folder fragments = 0
Master File Table (MFT) fragmentation
Total MFT size = 81 MB
MFT record count = 79,838
Percent MFT in use = 96 %
Total MFT fragments = 2
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Fragments File Size Files that cannot be defragmented
None
PS. I run defrag all the time on this partition and all others, they all got 16k cluster except one FAT boot partition, 6 in total.