Tim is a BAMF as well as an excellent detective and I need to see more fics using that as a tag. OK? Ok.
You can't tell me the guy who went and saved batman at least twice one of which he wasn't even allowed a suit he was just vibing in jeans a hoodie and a homemade mask before his training was complete, in fact that's how he got the job, by saving batman, isn't a BAMF. That's not how this works.
Ra's Al ghul respects him. For a goddamn reason. He has canonically beaten multiple of his teachers = arguably he has evolved to become a case of student outlearns the teacher, and wasn't the assassin tournament purely for those of extreme skill?
He has learnt from the best and worst of his teachers. He knows how to do they're best manoeuvres and how not to make their mistakes. For example, asking for help when needed. (And finding alternate routes if it's not given) He was taught back when Batman was harshest to his Robins- debatably, this means he can take a harsher beating, and/or has a stricter skill set.
He successfully stalked Batman, and Dick Grayson and quite possibly the other heroes too. And even ignoring the fannon tim-has-been-directly-stalking-them-for-years, he did successfully stalk Batman and get the photos to give to Dick. He stalked Dick enough to know where he'd gone even when the Titans didn't, and knew where he lived, even as no-one else knew he knew. This indicates that he's amazing at stealth- possibly better than Batman himself, as he had no training in this prior.
He has clear analytical skill which he uses to outsmart Ras Al Ghul despite being in an arguably severe depression at the time, and presumably uses the knowledge he gains from that analysis ability. He's gained Ra's respect as a Detective.
Not to mention the Council of Spiders. Extremely effective Killers, thay killed the League if assassins (a group generally considered to consist of some of the most deadly assassins in the world) for sport. A single Spider killed whole groups of assassins at once. And Tim took on seven of them and won.
I could honestly go on and on. The other characters are also bamf and extremely cool as well, don't get me wrong, but Tim Drake is not the weakest member of the batfam.
I think (I may be wrong but I think) that this misguided belief comes from 3 main places:
1. He won't kill. (I argue however, this is his strongest trait. His morals is so strong he stopped Batman at his lowest, however, unlike batman, he has a good balance of not killing and being able to work with Killers if and when needed). But this is a sharp difference to the multiple assassins in the Family, and Jason and damian who have tried to kill him. I argue that if Tim decided he wanted to use lethal force against them he would have won, because he knows their weaknesses and let's them underestimate him, but he didn't use that full skillset, which was probably a smart manoeuvre as he can now use it if anything goes too far
2. He doesn't always use his full power or moves or skill set. For example, I rarely see him utilising his skill with a slingshot. This is a calculated manoeuvre however, makes his full skill a card up his sleeve, and one of the lessons he was taught by Lady Shiva- let them underestimate you, it will be their downfall.
3. A bo staff, in comparison to guns, swords and electric charged staffs seems less dangerous. However, ignoring the fact that it has a knife in the end, it's actually a very dangerous weapon, and generally agreed that Tim chose it because it was the least lethal out of all the options he was given to lesrn; this means 2 things- 1. He was probably taught how to kill with it, so unlike others who need a specialised weapon, give this man a stick and he'll be fine, and 2. It implies that he knows just how deadly he could be with other weapons.
4. Fannon depiction, particularly of his poor mental health leading to a misguided impression of Tim being akin to a kitten soaked in the rain, rather than a rather yes, whilst being a poor-mental-health suffering character, he is actually still extremely dangerous, honestly more dangerous the worse his mental health gets. Tim has his lows and poor mental health, but for some reason I find that fics seem to depict him as being less able to function, when actually, the guy's response to poor mental health is extremely intelligent (if misguided and kinda manic) cloning attempts, and taking down the league of assassins and council of spiders at the same time, and similarly to Batman, becoming harsher and crueller against foes in the face of grief. Also, this angsty period isn't the entirety of his era.
Anyways, I could ramble forever, but I'll stop there.