I've cast my 'vote'. I do collect BA miles and points.

I've been a member of BA Executive Club for many more years than I can even remember. Since I left my 'travelling job' 10 years ago I haven't been anything like a frequent flyer. In fact I.ve gradually used up nearly all my air-miles during that time.
I will remain a BA Executive Club (Now called Avios) member for as long as I can.
There are plenty of benefits if you take time to read the small print, use the points wisely and get the biggest 'bang-for-your-buck'.
Many frequent flyer schemes can work out the same or even higher cost on many routes once you look at the tax to be paid.
Often better to use your rewards for upgrades on flights or for hotels.