I don't think I agree with the bolded. Long term? I could see Alexandrov developing more scoring ability than Leivo. But Leivo dramatically outscored him at the AHL level last year and was the playoff MVP purely based on his insane production. He's scored at a 29 point pace through 200+ NHL games in largely 4th line usage. He scored at a 35 point pace in Vancouver (the only time in his career that he's played 3rd line minutes).
I value that track record much more than I value a few preseason games and a good 5 game AHL start for Alexandrov. Especially since we're talking about a roster spot that is only going to get in the lineup when the team has injuries. I don't really want a 22 year old Alexandrov shuttling up and down to occasionally fill in for short term bursts.
I like (what looks to be) the Blues strategy here. Use Leivo and Pitlick to plug temporary holes for the next couple weeks and hope we get healthy sooner than later. Leivo will have to clear waivers again in 12 or 13 days, so I'm guessing that the hope is to get healthy by then and then ship him down to the AHL without exposing him to waivers. Or to pass Pitlick through waivers and assume no one will claim him since any team could have given him a contract until now. Either way, one guy stays up to be a press box guy when we're fully healthy. Hopefully that remains the case for a while and our next AHl recall is multiple weeks down the road. If Alexandrov is still looking good in the AHL, consider calling him up then.
I reject the argument that Leivo is a better NHL'er than Alexandrov. Leivo primarily played with Pettersson, Horvat, Boeser, Pearson, and Spooner for the majority of his time (that I could tell). He got significant time on the powerplay and was consistantly on Horvat's wing. He was also playing ~15 minutes a night, but regularly got 16-20 minutes a night depending on the situation and scored at about a 35 point clip in Vancouver. The rest was about a 25 point clip (but this includes his short stints in Toronto under 20 games). If we get rid of these instances, its about 20 points per 82 games, but I'm comfortable with saying between 20-25 points playing about 10-11 minutes a night. Now, This doesn't necessarily mean that he was "trusted" in Vancouver and that's why he got powerplay time, but it's pretty easy to see that team was highly flawed and that's why he got so much playing time.
My assumption is that Alexandrov would be playing some 4th line, occasionally 3rd, and likely depending on the practices, we might even see him get chances much like Barbashev where he is in the top 6. My contention is that while yes, he has scored significantly less than Leivo in the AHL, he has shown in his limited amount of time that he can play a good two-way game, or a game that reflects the Blues game much better than Leivo, and I have confidence that over 82 games, he could reach 15-20 points playing on the 4th line. This is evidence of the fact that he played the pk and pp in junior (maybe in Finland also but I can't attest to that) and the AHL. he was drafted as a player that plays a two-way game as well, and he also had a good camp deserving of at least a handful of games to start the season.
If your argument is that Leivo has more experience in the NHL and that's why he should get the nod over Alexandrov, then I can't really argue against that, but just based on play style and his performance thus far, I'd much rather have Alexandrov playing up and down the lineup until we're healthy rather than Leivo.