not sure I would spend money to upgrade to lockout only. Spend to upgrade for a better fork that also comes with lockout – yes.
ie lighter, better damping, lock out etc.
Only time I use it is on fire roads, road, smooth climbs – but as they are not the main reasons I ride my bike it is not the most important part of my riding.
I have a poploc (remote lock out) which makes using the lock out easier so maybe I don’t think about it and just use it compared to having to make the effort to reach down and flick the top of the fork but tbh 90% of the time you use the lock out reaching down is not any hassle. Being able to release it quickly from the handlebars when you are airborne and remember its still locked out is handy though 😀