Common to MacArthur and his commentaries he forces his point of view rather than illuminating the difficulties of translating the passage.
If the NASB desired to make this verse gender neutral they did a very poor job of it.
No, they were using an dis-gendered definition of the Hebrew word for "might one" [not cis-gendered ;-)]
גִּבּוֹר - a mighty one— a person noted for physical strength; often related to fighting ability.
Ge 10:8 לִֽהְי֥וֹת גִּבֹּ֖ר בָּאָֽרֶץ׃ - ...he became a mighty one (or mighty man) on the earth
2 Sa 1:19 הַצְּבִי֙ יִשְׂרָאֵ֔ל עַל־בָּמוֹתֶ֖יךָ חָלָ֑ל אֵ֖יךְ נָפְל֥וּ גִבּוֹרִֽים׃ ...How the mighty have fallen
Joel 3:9 הָעִ֙ירוּ֙ הַגִּבּוֹרִ֔ים יִגְּשׁ֣וּ יַֽעֲל֔וּ כֹּ֖ל אַנְשֵׁ֥י הַ ...Prepare for holy war; stir up the warriors! (or mighty men)
Amos 2:14 וְגִבּ֖וֹר לֹא־יְמַלֵּ֥ט נַפְשֽׁוֹ׃ ...the strong will not strengthen his power, nor the warrior save his life.
I personally like Robert Alter's recent translation (2019)
For the Sun he set up tent
and he like a groom from his canopy comes,
exults like a warrior running his course.
Note: the description in the last stanza is describing actions of the Sun.
Lastly, if the NASB wanted to pursue gender-neutrality here, why would they include the masculine pronoun there?
The last word of the stanza ("course") has no pronoun attached to it but in translation it borrows its pronoun from the second couplet ("
his canopy").
No, this is MacArthur's groupies simply acting pompous again to push sales of his Legacy Bible.
Rob