I am wary of the so-called 'progressive' Hindus. They do not respect traditions. If there are other 'progressive' Hindus other than Bengalis, I would be just as wary of them.Zoroaster was an Aryan brahmin but not Hindu. I wonder how he arrived at the conclusion that there is only one God and not many. Spitama Zarathrushta. I checked, no Vedic sage with that name is mentioned. I think he belonged to was the line of sage Atharva and not Angirasa. That is why the evil spirit became Angre Mainyu.
"The Ṛig-Veda mentions a number of ancient sacrificers styled our fathers (II, 33, 13; VI, 22, 2), who instituted the sacrifice in ancient times and laid down, for the guidance of man, the path which he should, in future, follow. Thus the sacrifice offered by Manu, is taken as the type and other sacrifices are compared with it in I, 76, 5. But Manu was not alone to offer this ancient sacrifice to the gods. In X, 63, 7, he is said to have made the first offerings to the gods along with the seven Hotṛis; while Aṅgiras and Yayâti are mentioned with him as ancient sacrificers in I, 31, 17, Bhṛigu and Aṅgiras in VIII, 43, 13, Atharvan and Dadhyañch in I, 80, 16 and Dadhyañch, Aṅgiras, Atri and Kaṇva in I, 139, 9. Atharvan by his sacrifices is elsewhere described, as having first extended the paths, whereupon the sun was born (I, 83, 5), and the Atharvans, in the plural, are styled our fathers (naḥ pitaraḥ
along with Aṅgirases, Navagvas and Bhṛgus in X, 14, 6. In II, 34, 12, Dashagvas are said to have been the first to offer a sacrifice; while in X, 92, 10 Atharvan is spoken of, as having established order by sacrifices, when the Bhṛigus showed themselves as gods by their skill. Philologically the name of Atharvan appears as Athravan, meaning a fire-priest, in the Avesta, and the word Aṅgiras is said to be etymologically connected with the Greek Aggilos, a messenger and the Persian Angara a mounted courier. In the Aitareya Brâhmaṇa (III, 34) Aṅgirases are said to be the same as Angârâḥ, burning coals or fire, (Cf. Ṛig. X. 62, 5). Whether we accept these etymologies as absolutely correct or not, the resemblance between the different words sufficiently warrants the assumption that Atharvan and Aṅgiras must have been the ancient sacrificers of the whole Aryan race and not merely of the Vedic people. Therefore, even though Manu, Atharvan, Aṅgiras be not the names of particular individuals, still there can be little doubt that they represented families of priests who conducted, if not originated the sacrifices in primeval times, that is, before the Aryan separation, and who, for this reason, seem to have attained almost divine character in the eyes of the poets of the Ṛig-Veda."
People generally know my source so I need not mention it.