In Europe
Purpose of these "hygiene rinses" was for laundry that couldn't or shouldn't be washing in hot or boiling water and or dried in a hot dryer. That and of course couldn't be subjected to bleach, chlorine or oxygen. Things like Lycra and other man made fibers, and or "fine laundry".
These were important as the move for female "intimate apparel" began to move from pure cotton or linen to various wholly or partially man made blends. In order to cope with a bout of; well, yeast infections, and or for women prone to such or had other issues, these rinses were meant for their undergarments that couldn't be "sanitized" by normal laundering methods. For the men it was athlete's' foot and socks that again could not withstand harsh laundering.
Persil and others latched onto the increasing trend of not only warm or cold water being increasingly used for laundry (all those "turn the dial down" advert campaigns), but the fact many items of clothing or household textiles come with care labels specifying "warm or cold wash, no bleach".
Unlike decades ago when everything was mostly pure cotton or perhaps linen, and was white or colorfast, much clothing or textiles today are colors and or made from fabrics that cannot (in theory) be subjected to the hot and often harsh washing of past. So to add the measure of "security" you use a sanitizing laundry rinse.
There is also the trend towards using liquid detergents which not only do not contain bleaches, but lack the sanitizing power of alkaline substances. That whiff you get in your kit or shirt underarms is normally taken care of by the fact human perspiration normally is acidic. Alkaline substances obviously will cancel that out, and in the case of some other substances such as Borax have (mild) disinfecting qualities.
Some liquid detergents in past and today claim and maybe do deal with "whiff", others not so much.
https://www.amazon.com/Persil-Hygiene-Disinfectant-Rinse-PACK/product-reviews/B0060CIT2S
All this being said, no, you do not need any sort of hygiene rinse, especially if using good hot water and a detergent with bleach, and or adding it separate. But for those who cannot or will not....