Extra weapon proficiencies from racial abilities does not matter. 9 times out of 10, characters that would want to use those weapons - will already have them from their class. And for those that dont - they rather be spending their action on a cantrip or spell.
Not entirely true.
Casters especially like getting Bow/Crossbow proficiencies because before level 5 Cantrips suck so bad compared to them (While Druids don't actually get a ranged option unless going Circle of the Spore). To say nothing about Clerics and their awkward cantrips pre-Spell Sniper.
Bow proficiencies overall are good because there's plenty of bows that provide passive bonuses for equipping them. So even your Fireball slinging Wizard can get something nice like +1 initiative, advantage vs monsters or fire + cold resistance (Plus a free Haste cast per long rest) just for having the bow equipped, even if they never use it.
Casters can also utilize hand crossbows well, since they can use their bonus action (That is normally unused) to shoot something. Be it actually hitting an enemy for the 1d6 damage or maybe they want to shoot a bottle of water to put Wet on enemies before using their standard action on Lightning Bolt/Call Lightning/Chain Lightning/Cone of Cold.
Even some melee weapon proficiencies can be useful.
A Monk getting to use Longswords for a versatile weapon which is good because it means they get a 1d10 weapon that still allows them to use their Bonus Unarmed Attack with the notable benefit of their being many very good Longswords in the game (While most staves are itemized more towards casters or have crap bonuses)
A non-War/Tempest Cleric being able to use Spears/Pikes/Halberds/Glaives can allow Clerics to utilize Polearm Mastery feat for a way to utilize their bonus action - Especially notable for Life, Nature and Trickery domains which get bonus 1d8 damage from their level 8 perk instead of the Potent Spellcasting that Light/Knowledge gets which makes their Cantrips better.
As far as the Light Armour proficiency... Honestly there's only 1 robe that I would care to actually use which is the CHR mod to Cantrips one. Meaning for a Wizard I'd rather use Spidersilk Armor (Or Barkskin Armor for a Shield Dwarf) for the advantage on Concentration checks (As they're a Constitution save) since not having my concentration broken is worth FAR, FAR more than +1 DC and getting it from armour means I can skip on the War Caster feat in lieu of something else (Like +2 stats for +1 DC, Attack rolls and Damage for EvoWiz. Or Dual Wielder to use 2 staves for their DC bonus and +1 AC)