As always you either believe that testing works or it doesn't. If you believe testing works, which Jakob seemingly does, then you ramp up testing (done), up minimum testing requirements by country (done), and do more targeted testing (done). The only other moves from there are to up the suspension lengths, criminalize doping (hard to do), and/or try to take down doping rings (being done somewhat, but also very expensive).
The last deterrence moves are banning entire countries/training groups for a doping positive, or alternatively coaches, agents etc. These moves have the potential of penalizing other athletes or staff who have nothing to do with the offense. You can say "well fair is fair," but be careful what you wish for when a Shelby situation could result in all of Bowerman Track Club getting banned.
It is interesting that Jakob thinks that testing is "definitely not working," when he loses one race a year to a Scottish guy and otherwise trounces every single runner in every other race (unless he's sick or doing a 24-hour double). He must have a pretty high opinion of his talent and training if doping is such a problem and yet nobody can compete with him.