Questions about the debuff impact of death

[NaiXizi]

When I communicated with other players, I heard that some jobs will not be affected by the debuff caused by this death. For example, SMN's Ifrit, Bahamut, Firebird, and Scholar's summons, I tested them and found that they really had no effect. Skills related to summons will not be weakened by this debuff.
** So I have a question, so are Machinist and Dark Knight?

[CKNovel]

Let's first take a look at what the debuff does:
-Reduces Strength, Dexterity, Intelligence and Mind by 25%

There's also other status with the same effect and for that we'll use the Potions and "medica.
Currently the highest Dexterity potion is an increase of 10% (Max 398 DEX)

The pets are supposed to be an extension of your character. Therefore they should benefits from buffs aswell.

Did some testings with and without potion and Automaton Queen's Arm Punch:
Between 6.800 and 7.300 damages without potion.
Between 7.600 and 7.900 damages with potion.

As there is an increase, the Automaton Queen is subject to DEX changes. Unless there is a special exception, it should work with Death debuff aswell.
But note that dying resets your gauges to 0 and desummon the Queen if present, so there IS a loss even if the Queen would not be affected by Weakness.

As for Summoner
Back in Stormblood, Bahamut was to be summoned every 2 minutes and the gauges resets meant that you had to restart from scratch.
This lenghty phase has been reduced. However, having your gauge reset means that you could loose the Firebird Trance aswell as Bahamuth Trance.

This special exception could exist and made to mitigate the impact of Death on "Pet jobs"

[Nemekh]

The main thing with potions and food is that they mirror from the master to the pet. When we get the Medicated status so does our pet same with our food buff. What differs is when pets do not have statuses mirror.

It wasn't always the case where consumable buff mirroring was added with HW release and with each expansion things were added to the list.

In 3.x AST cards did not mirror and single target cards could only affect the pet or the master. No buffs mirrored except consumable buffs.
In 4.x they changed that so cards always mirror. Battle Litany, Battle Voice and Dragonsight did not mirror.
In 5.x they changed BL and BV to mirror. Dragonsight is the only player buff exception now.

Encounter specific buffs and debuffs tend not to mirror. Livewire, Neurolink debuffs in UCoB.
Exceptions exist, like Grace of Light in E8S and UCoB's Phoenix Blessing specifically buffing all entities.

Weakness/Brink to my knowledge have never mirrored. (I trawled through some old encounters to double check)

This all applies to:

AST Earthly Star
DRK Esteem
MCH Turret/Automaton Queen
NIN Bunshin
SCH Faeries and Seraph
SMN Egis/Demis

Addendum: Pets also do not benefit from the party bonus. The extra stats we get do not get transferred over.