TripAdvisor is powerful for some properties and very weak for others.
For us, it is pretty bad : their search engine is appalling compared with that of booking.com and it is very difficult for our property to appear in the results unless typing the name of our small village... Almost no one does it. Result, the fee for the business listing is far too high. Even though my booking engine can connect to TripConnect, I won't do it.
TripAdvisor was "best one first". Now, it is moving to OTA behaviour : pay or disappear.
Yes, looking for & booking a B&B in France is a lot of work. Websites outdated, no booking engine, no credit card guarantee, slow feedback from owners, ... Booking.com is helping good as more and more B&Bs have joined.
It will take time before it improves. Many are still using pen, paper & eraser to help tax evasion.