It’s not very common that these sensation changes stick around for the long-term. In other words, sensation will return as your nerves recover as your body heals from surgery. Surgery involves cutting so it’s a form of trauma to your tissues. This means nerves can get ‘injured’ during surgery.
We don’t 100% know the answer to some breast augmentation recovery questions because advice is based on either evidence (what we know works) or experience (what we have found to work). Some of the questions you ask won’t get a unified response. Some of the common bra recommendations have sensible reasons behind them though.