At my guild we have won our last 21 TWs. During that time we’ve never had a full 50/50, and I’d guess the average is about 42 or 43. We do make TW a priority, everyone has omi and team requirements, but players only sign up if they can be active in all phases. There’s no sandbagging though, it’s just people not having the time because of real life commitments. Last time around we had 32,l sign up, as a combination of people having commitments and a few people having strikes for poor choices in previous TWs (the first time in a while). No one was told or asked to sit out for a better matchup, and no one was in any of the previous 20 either.
I don’t buy that sandbagging happens because ‘someone in a guild told me so’ or because only 41 or 42 people signed up. If guild officers are ordering it then they’re d-bags and are only hurting their guilds, but I’d expect it’s the vast minority.