If you edit the activity there's an option to hide various stats, one of the options is to hide power.

https://support.strava.com/hc/en-us/articles/360028654291-Hide-Stats-from-your-Activities

Thanks, must I do this for each activity going forward or is there a global preference too?

oops!

>You cannot set a default preference to hide your activity stats. By default, all stats will be shown to other athletes, >but you will always have the option to adjust this setting on the edit or upload screen.

There's no global preference (as you found), but there are 3rd party apps out there which can do it for you. I'll plug my own - https://www.activityfix.com 🙂

Hello and thanks to everyone who has posted about this.

Athletes can now set defaults for which details are hidden so they do not need to be reset on each activity. The stats that can be controlled include Start Time, Pace, Speed, Calories, Power, and Heart Rate.

Default settings can be found:

• In the app, by going to the account settings menu from the You tab > Gear icon > Privacy Controls > Hidden Details
• On the web, by going to the Profile Menu dropdown > Settings > Privacy Controls.

Setting defaults will not hide stats retroactively; it only affects activities uploaded after the setting is saved. Please refer to the link below for more information.