It would depend on the audience I think. The senior arahants did teach students and in that case they would speak at the level of stream-entry. For example in SN 22.122 there is another question-and-answer session between Ven. Maha Kotthita and Ven. Sariputta where stream-entry and the other levels of attainment are specifically designated. But MN 43 seems to be an exhibition talk on psychological subjects directed to an advanced audience, and freedom in connection with arahants appears about fifty times in the sutta. There is a report these question-and-answer sessions were staged in Thailand in recent times.
These suttas fall under the last category, relating to religious teaching by means of questions and answers (Piya Tan):
sutta the discourses, ie prose passages; eg Sutta Nipāta prose passages, Niddesa,
Vinaya, Vibhaṅga, and texts with “Sutta” in their titles;
geyya the mixed prose and verse, such as the Sagāthā Vagga of Saṁyutta (S 1), Kasi
Bhāra,dvāja Sutta (Sn 1.4);
veyyākaraṇa the expositions, ie elaboration of brief teachings of the Buddha;18
gāthā the verses, eg Dhammapada, Thera,gāthā, Therī,gāthā, Sutta Nipāta verses;
udāna the inspired utterances, especially Udāna, also M 1:171, V 1:1 ff, etc;
iti,vuttaka the sayings, ie the Iti,vuttaka;
jātaka the birth stories, such as those in Kūṭa,danta Sutta (D 5,10-20), Mahā Sudassana Sutta (D 17), Mahā,govinda Sutta (D 19,29-61), and the Jātaka verses;
abbhuta,dhamma the marvels, special qualities of disciples;19 and
vedalla the answers to questions (catechetical suttas):