The Properties and Algorithms group has discussed this issue; it will likely be proposing at UTC #175 (April 25–27) that a new definition Unicode standard encoding form be added to mean the three UTFs, and that references to the [three] Unicode encoding forms throughout The Unicode Standard be fixed using that new definition.
If such a proposal is accepted by the UTC, the resulting change would make it into a published standard no earlier than Unicode 16.0, September 2024.
Dear SG 16,
There has been further discussion of this issue in the Properties and Algorithms group, with some alternatives being proposed to avoid the disruption that a new definition could cause, while still making it easier to refer unambiguously to the three Unicode encoding forms defined in the Unicode Standard.
Progress on this issue is ongoing in the PAG, but since the UTC is this week, the proposal is not in the PAG report for UTC #175 (see Section 1 of L2/23-079
This does not change the expected timeline for publication, since Unicode 16.0 is still quite far away.