I installed krita 417 and it does the same thing. pressure is recognised though, both in 417 and 42. It was just not that obvious with the pencil I used in the image.

using the same pencil in both 417 and 42, I noticed that the angle effect is more pronounced in 42

installed 421 and this is the result with the basic-5 brush. I added the window for tablet testing which looks fine:

https://my.pcloud.com/publink/show?code=XZpivA7ZzQstNPP2laSC8K2ReCrcxyXB3JLV

What tablet brand?
Which version of macOS?
Which smoothing type have you selected for the freehand brush?
Do you have canvas acceleration enabled or disabled?
What GPU does your mac have?

That is bad,

Does it improve if you turn off canvas acceleration in "preferences > display"

I have a macmini 2018 with Intel UHD graphics 630 1536 MB

OSX 10.14.4

Wacom Cintiq pro 24 (resolution 4608 x 2592)

Open GL is on,
smoothing is none

if I turn on smoothing to basic it gets better but is not gone. The circles are more rounded, but now and then they still have strong angles.