Workhorse

n.capable, resilienteveryday

What it means

A dependable person, tool, or system that handles a large share of useful routine work.

Reach for it when praising sustained reliability while avoiding language that normalizes exploitation

The old laser printer remains the office workhorse.

playful
heavy lifter
when carrying the largest burden should sound informal
not when Heavy lifter can excuse unfair workload instead of offering dignified recognition.
playful
old reliable
when affectionate familiarity with dependable equipment fits
not when Old reliable is informal and can reduce a person to availability.
warm
backbone
when something essential supports the whole operation
not when Backbone is a stronger structural claim and can romanticize invisible labor.
warm
mainstay
when ongoing importance and dependable support are central
not when Mainstay can provide stability without doing a large volume of routine work.
professional
reliable performer
when consistent results should be stated without metaphor
not when The phrase does not convey the large workload carried by a workhorse.
professional
utility player
when versatility across roles is the strength
not when A utility player covers variety, while a workhorse may repeat one demanding task.
literary
stalwart
when loyal durable service deserves dignified praise
not when Stalwart is person-focused and sounds old-fashioned for equipment.

reliable workhorse
The reliable workhorse processed every nightly backup without attention.
office workhorse
A repairable copier became the office workhorse for twelve years.
team's workhorse
The team's workhorse also received protected time to train a backup.

Calling a person a workhorse can praise endurance while hiding overload. Name their contribution and ensure the workload is fair.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.