Unable to remove Windows partition on Boot Camp partition

I have installed Windows Boot Camp partition and installed Windows 8. Later, I upgraded to Windows 10.

I am unable to remove Windows partition using bootcamp assistant. The removing Windows option is greyed out.

diskutil list
 /dev/disk0
   #:              TYPE NAME                    SIZE     IDENTIFIER
   0:      GUID_partition_scheme              *121.3 GB    disk0
   1:                        EFI               209.7 MB    disk0s1
   2:      Apple_HFS Macintosh HD               70.0 GB    disk0s2
   3:      Apple_Boot Recovery HD              650.0 MB    disk0s3
   4:      Microsoft Basic Data BOOTCAMP        50.0 GB    disk0s4
   5: DE94BBA4-06D1-4D40-A16A-BFD50179D6AC     471.9 MB    disk0s5

I found that the only way to remove a bootcamp partition and make it a fully MacOS partition is to wipe the drive and reinstall macOS. Bootcamp utility says it can remove the bootcamp partition and resize the MacOS partition, but it doesn't work. Please tell me if anyone has gotten it to work.