I believe if they could get Bale then they would have, but Traore have been in the premier league and he is not as expensive when you look at the salary differences. Bale is great and all but he has a very high salary so that is the biggest difference. Which is the main reason why they are probably looking at him. Plus Traore is 25 years old and that is a big difference to be fair, if a player is 7 years younger than you could get that player and then make them play a bit better by fitting them into your strategy as well.
So, this is not a horrible transfer choice to be fair, yeah I would agree that if you could get Bale for free and get him to accept a very low salary then you would prefer that, but if not then I would say that Traore with cheaper salary and 7 years younger looks like a better deal to get done, you can get more out of him.
Gareth Bale can really cost Tottenham much higher than Adama Traore in terms of wages. But I'm still not sure about whether bringing Traore would still be a good choice. Because in this case, Antonio Conte will have a big responsibility to help him improve his performance a lot. Because his current level is definitely not enough to be able to play and be productive for a top team. If Conte helps him improve himself and reach a much better level compared to now, it would be really great. But there is no guarantee for this to happen.