With respect, you write as though you aren't interested in hearing explanations and aren't open to altering your position, so I'm not sure if there's any point or value in responding or trying to be helpful here - if I'm mistaken I apologise, but that's how your tone reads. Regardless, if if helps your concern, here are some things to consider:
Here's your first problem. This is not an MMO. This is a single player party-based, story-driven RPG, with the capacity for multiplayer support. It's a game (very loosely) based on Dungeons and Dragons, also not an MMO.
Bards are a unique and suitably strong class to play, capable of being highly flexible and leaning into a broad variety of roles more easily than almost any other class, depending on what choices you make. Larian may not have done a great job transposing them into a video game, but they're still their own thing, even here.
If you feel like you'd enjoy playing sorcerer more, then play sorcerer. If you feel like you'd enjoy playing Cleric more, play cleric. If you're not interested in character or roleplay and only interested in raw crunch numbers and mechanical value, then there are only one or two classes that you will ever play, and only with one or two specific build styles... but I'm going to presume your needs for mechanical validation doesn't stretch quite that far, as it does for some.
Can your cleric cast hypnotic pattern, charm person, faerie fire, hideous laughter or see invisibility? No, they can't...
Can your sorcerer cast Cure wounds, healing word, lesser restoration, Silence or Heat Metal? No, they can't...
Your Bard can do both of those things, at need, and can suitably do the job of your Wizard, your Cleric and your Rogue all in one package - maybe not quite as well as one dedicated to those specific roles, but definitely well enough to fill the role and with the capacity to pick up the slack if things get messy - they can fill in for your healer if your healer drops, they can fill in for your crowd control if your controller drops, and they can bust your rogue out of gaol and steal his stuff buck when he inevitably gets caught because he was too cocky... if that's what you'd like them to be able to do.
Bards in D&D can indeed buff the party and themselves - they have more access to buffing, debuffing and support spells than any other class, as well as access to the majority of important healing and restoration, which is something that arcane casters are otherwise hard restricted from with very few exceptions, and all that at base and before specialisations are taken into account. They have an additional unique ability to buff other party members (and sometimes themselves depending on their college choice and level), that no-one else has access to and which stands aside every other possible buff and stacks with them in ways that most other spells do not stack. Bards also have the least combat focus of any class, with a decent portion of their skill value being centred around skills and non-combat situations; it's often considered harder to make this shine in traditional video game, but modern rpgs create spaces for those elements to come into play properly.
Larian's implementation aside, Bards are an excellent and fulfilling class.
