The Astros have drafted a lot of very good players but even they don't have a blemish free history of first round draft picks and we shoudl be very familiar with that!
Between 2009 and 2015 the Astros selected 13 first* round players. Six of those players have made the majors so far. I think its unfair to judge their picks form 2016-2018 too harshly yet as they are still progressing their the minors. So 6 of 10 have made it to the majors.
Those 6 players have combined for 55.9 fWAR and 57.1bWAR which is very impressive but that is mostly made up by three players, Springer, Correa and Bregman.
2009 - Pick 21: Jiovanni Mier - has not made the majors - After 10 years I think its fair to call that pick a bust
2010 - Pick 8: Delino DeShields Jr. 4.1 fWAR, 4.2 bWAR. Not a complete bust but not exactly a success either. Hes a marginal role player at best, which is useful but for the 8th pick you probably want more.
2010 - Pick 19: Mike Foltynewicz: 6.9 fWAR, 4.1 bWAR. Strange one, he had been below replacement and then average between 2014 and 2017 but was an all star in 2018. Interesting one to track going forward as he is in his age 27 season, was 2018 a one off or is this who he is now? He was traded as part of a package for Evan Gattis (5.4 WAR for the Astros) and a player who has not yet made the mahors. Overall probably a good pick for the Astros.
2010 - Pick 33 Mike Kvansnicka - has not made the majors - After 9 years I think its fair to call that pick a bust
2011 - Pick 11: George Springer - 18.2 fWAR, 18.7 bWAR. Probably their best value pick for the position. Also won a World Series MVP which doesn't show up in the stats and is very valuable.
2012 - Pick 1: Carlos Correa - 15.3 fWAR, 18.3 bWAR. A very good pick, any team would be happy with the level of production he has provided.
2013 - Pick 1: Mark Appel - has not made the majors, is a complete bust. Is he even in baseball anymore? They did manage to package him along with Vince and two other eventual nobodies for Ken Giles who helped them win a world series, so they are probably happy overall but the draft pick was not used optimally.
2014 - Pick 1: Brady Aiken. has not made the majors, isn't in organised baseball anymore and they didn't even manage to sign him, so a complete bust except...
2015 - Pick 2: Alex Bregman. fWAR 12.1, bWAR 12.7 They turned that failed draft pick into a star who has already helped them win a World Series and is only 2014
2015 - Pick 5: Kyle Tucker fWAR -0.7, bWAR -0.9. Only reached the majors last year so a bit early to write him off.
2015 - pick 37: Daz Cameron. Has not made the majors yet.
They originally had 4 picks in the top five, including 3 number 1s and two of them were disasters. However they turned one of those disasters into a number two pick who is a star and traded another as part of a package for a closer who has been hit and miss but who did contribute to a WS.
Its not too different from what the Sixers did with 4 top 3 picks between 2014 and 2017. Astros got Correa and Bregman. Sixers got Joel and Ben. Springer is the key difference.
I'd definitely take their draft success but it shows that number 1 is rarely a guarantee.