Dwarves can grant themselves Tremorsense multiple times a day.
Tremorsense could be nice for peeking past doors/walls/to other floors of the building, but... it's a really subtle ability that is
very prone to GM interpretation.
TREMORSENSE
A creature with Tremorsense can pinpoint the
location of creatures and moving objects within
a specific range, provided that the creature with
Tremorsense and anything it’s detecting are
both in contact with the same surface (such as
the ground, a wall, or a ceiling) or the same
liquid.
Tremorsense can’t detect creatures or objects
in the air, and Tremorsense doesn’t count as a
form of sight.
You know where creatures are, but you don't know
what they are.
'hey guys, there's something moving behind this wall'
'what kind?'
'I dunno'
'gee, very useful, dwarf scout'
By rules text, you might not even be able to know if they're small or large, though logically you should feel the difference in tremors/pressure.
You can automatically tell where someone hiding is (yes, even if they're still), but you'd have a disadvantage to attack them regardless (does not count as a form of sight). Dwarves having this ability seems to have more of an impact against player parties ('oh no, they have a dwarf with them, guess stealth is useless') than
for player parties.
Its best use (for common player situations) would be as a safety check when stepping into a house/lair, to see if you're safe or if there is anyone around (and where), but again, we run into GM interpretation meaning that you might not know if the three signals from upstairs are people... or mice in the walls.
When other races offer concrete benefits like d12 damage reduction, movement speed increase, better mental saves, avoid being dropped to 0hp, extra spells for casters... tremorsense as the uniquely dwarf-defining feature just doesn't stack up. Getting +1hp/level is okay, but you could just be a human and pick up Tough with your extra feat for twice the effect (and this racial also has the weird effect that dwarves are better for small hitdie classes, like wizards).
Dwarves aren't the worst (now that they get 30ft movement), because Dragonborn and Tieflings also exist in the same design realm of resistance+ribbons (Dragonborn flight solving a common melee problem would be amazing... if it wasn't just once a day), but dwarves are not any stronger than they were in 2014 PHB (where they at least had the option of getting +2str +2con to start with).