LACAllen, every thing you say, as well as how you say it, is in no way bothersome. To those who don't necessarily know the significance of a rich text client or whether an app is one, the messaging app does come across a something of a word processor. When I Google "where is iphone BIU button," unaware as I was it's not possible in messaging the first response is:
Double-tap a word to highlight it and drag the indicators to select multiple words if you want. Then, a menu will pop up. Tap "BIU" here, then select from one of the four options: Bold, Italic, Underline, or Strikethrough. Depending on the app, you may not see this option in the popup menu right away. Mar 27, 2020
Bottom line, you're coming from a horse of ordinary height and not in any pedantic.