(Actually I've had a few lately, has the TPS been abolished or what?)
No, not scrapped, but some firms seem oblivious of the penalties (I think up to 5K fine per 'bad' call), and some seem just not to care.
However, it is worth going back to the TPS service and registering the number again every 2 years. The worst you can get is a message from the site saying "that number is already registered" (at which point you have some peace of mind).
FWIW, it is free to be unlisted in the directory database. There are 3 (or 4 if you are some MoD or government top bod) where
1) is unlisted (but your details will be given if a person asks for you by name and gives correct address
2) unlisted where number is not released even with correct name and address
3) unlisted, and operator will intercept calls, ask caller for their name, call your number and ask if you want to talk to them (this one has a fee, last time I looked it was a 100+ a year, but I could have misremembered!)
- unlisted, and not even on Openreach database (for top security people so number cannot be found by bribing staff).
The directory database is managed by BT (as they still have majority of customers) but distributed to any firm (eg those offering 118 services) but your privacy is kept to one of those 4 levels, and you would have to request a change to 1/2/3 either with BT or the company you use.
Level 1 still means any organisation (such as a school) could get your number via enquiries but it would not be listed online or in printed directories.