@Hannes Drexl and all, keen eye! Thanks for bringing this up.
This was an intentional change since there has been a bit of UI creep in the tool options bar from both the left and right sides and some options were starting to overlap. We made a decision to remove the anti-aliasing dropdown from tool options to reduce this overlap for folks with lower monitor resolution according to minimum system requirements.
As some have mentioned, these options are still available in Character panel, Prop
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