I think tournament penalties may be lower because tournaments can result in lots of players running out of time (often without meaning to). My first tournament, I thought the timing was 12h per move, not 12h total for the entire game. I was out of time within the first day of the game.
Now I don't play anything less than 48h per player (usually preferring 72h per player), but I still regularly get timed out due to timing issues (players who play in the early part of my sleep period). I'm on here 4+ times per day, but that does nothing in a tournament setting - if the other player is missing during my daytime hours, we both run our clocks out, and if they're present, I get a couple moves in, only to lose another 5+ hours overnight. I don't run out of time in regular games very often (only when life REALLY gets in the way, and I don't get on for over 24h) but I run out in tournaments regularly. Escalating penalties would be the final nail in the coffin for me playing tournaments at all.
I do get what you're saying about no-shows, but that's a very different penalty to someone who is doing their best to play regularly but their timing doesn't fall evenly with their opponents. I used to think this was a timezone issue, but as someone pointed out, even for 4 players in the same timezone, someone eventually goes to sleep, someone else becomes the last player of the day, and their clock ticks all night. Yes, playing hours exist, but I've never seen a tournament where half the playing period wasn't during my sleep time anyway, so if anything, that would just be worse. Unfortunately there isn't a way to distinguish between someone who never shows up at all, and someone who is doing their absolute best and playing turns regularly, but is just unlucky with the timing.
