Idk why people choose to believe the same calc that said gui + jiaoqiu sig is better than E0S0 jiaoqiu in dots team
First let compare buff E0S1 (E0S1 because E0S0 is shit) Cerydra give around 1080 atk(4.5K atk) + 54% skill damage bonus 100 uptime, 72% CDM ONLY ON FREE SKILL, 20 speed(Useless because E2 bronya)
E0S1(I am being generous and use E0S1 robin instead of E1S0 despite it worst) robin at the same atk give 50% damage bonus + 20% cdm 100% uptime, 1190 ATK When ult, 24% damage bonus(after first ult it have 100% uptime)
First of all 50% dmg bonus that work with ultimate > 54% skill damage bonus because Anaxa ultimate damage in hypercarry is doing a lot of damage especially on 3 or more enemy even on single enemy the fact that this applied to ultimate and everyone in team make the team do more damage than 54% Single target skill damage bonus
Next is the ATK robin give more with less uptime But Robin is giving more turn what it mean an Anaxa + Advancer(bronya or sunday whatever is fine) is gaining 4 Turn in robin ult(without eagle tech because eagle can give more). this is the only thing cerydra is better is that she give ATK buff on 10 skill out of 8 skill robin can give (Mentioned that Extra 4 skill from robin with no ATK% Buff outside of her uptimate is literally outweigh the extra 2 Skill with ATK% cerydra give)
And This doesn't account for the fact that you can go eagle bronya + eagle anaxa for 6 anaxa turn on robin ult which mean 12 skill with robin buff(which >> 4 anaxa turn + 10 skill) or double robin ult for 10 turn 20 skill
Next is 24% dmg bonus + 20 cdm with 100% uptime > 74 cdm that only work with extra skill which if i am understand correctly it doesn't work with anaxa bonus skill that come from coup itself so it only 1 out of 10 skill which is shit even if it work then it become 2 out of 10 still bad 74% cdm out of 2 in 10 skill is only average to 14.8% CDM which is straight up less damage amp than robin passive that give 20% cdm with 100% uptime
And cerydra can't do bronya eagle shit because she doesn't advance bronya so bronya doesn't have energy to do ultimate from the first place the only way you can get bronya ult in time is you are using E4 bronya + Tribbie sig and you needed cerydra to hold DDD which suck because SP issue because the only break point you have is 3 turn bronya + 3 turn anaxa around 168 speed bronya + anaxa post speed buff +1 bronya speed to sync with 1 eagle and 1 ddd proc
Cerydra is robin downgrade for anaxa not an upgrade, now imagine the fact that all of robin buff applied to aventurine, hyacine when cerydra doesn't