Give a 10 second penalty and if the driver does something that would warrant a further 10s penalty then give them a drive through.
Did they actually get rid of drive through penalties or is it just something where there hasn't been an incident serious enough to warrant it?
Drive through still exist, Lewis just got one for being way over the pit speed limit.
But most of the time these drivers are not doing enough clearly dangerous moves that a drive through is warranted. People can hate on Mag all the want, but nothing he did in the sprint was dangerous. Against the rules of course, but not actually dangerous.
And the thing with drive throughs is that the cars are so close now that pretty much any car getting a drive through except the very front might as well just leave the race after getting essentially at least 25+ seconds on their time.
Back when drive through were more prominent, the top cars could also lap all the rest of the field easily and getting 25+ seconds was not impossible to make up. That is pretty much how it is today, so we should be careful what we wish for. I don't think races become better if they feel this dictated by stewards.
But generally I also just feel like rules changes have made stewarding worse. The standing that they never warn drivers that they need to give back a position, simply leads to stupid scenario's where teams don't believe they'll get a penalty (since many calls are not exactly black and white), so they don't give the position back and then they get a penalty without warning and their race is done, since it is at least 10 seconds on their time, which sends them back 4-6 places.