The problem with the usual methods
Reading a WiFi password aloud works until someone mishears one character. Taping it to the wall works until visitors photograph it, and the photo ends up synced to someone else's cloud. Texting it works, but the password now lives in message histories on every device involved.
None of these are disasters for a home network, but the same habits break down in offices, cafes, rentals, and guest networks where more strangers pass through.
Better options for homes and offices
Where possible, create a separate guest network with its own password you can rotate occasionally. That contains risk without changing the main network credential.
When you do need to send the password, skip the group chat. Paste it into a secure encrypted note, set burn-after-read, and send the link to your guest. They view it once, connect, and the password vanishes from the conversation. It takes under a minute and works just as well for a houseguest as for a conference room.