I don't rate him as better than Lenglet or Pique right now. But agree he can start for the current team.
Fair enough even if I disagree. I think he's better than both of them. But more important, we've all seen way too many times that Pique and Lenglet just can't work together as they're both too slow.
As long as he's fit Araujo is a must starter for me as he's the only one who brings physical and athletic presence other CBs (except maybe Mingueza; I consider Araujo as a better player than him and don't think they would fit well together so don't see an option of them starting alongside each other unless we'd have no other options) don't have. Sure, he doesn't have enough technical abilities for what most consider is a must for a Barca CB (he has improved a lot in that aspect since he first came to Barca B and possibly still can, will almost surely never become an elite passer though) but I'm just tired of these slow/weak great ball-playing and poor defending Barca DNA CB types the club loves so much.
Even in our best years we've combined a "technical" CB like Pique (obviously also a younger and more mobile than 2018-21 versions of him) with "warriors" like Puyol, Masche and even Abidal in some extent who opposing defenders were affraid off or at least respected them a lot more than they do our defenders nowadays. But since they've left football has evolved into a even more athletic and physical game we can't keep up with anymore without adapting our philosophy and recruiting to the demands of modern football unless we'd find a way to get again so technically superior to the opponents as we were during Pep's years which is almost impossible.
That said, even if I consider Eric in that typical current day Barca CB category I also think he and Araujo could complement each other well so in absence of better alternatives this season I'd like to see how they'd do paired together in a 4-man defense. Pique's time is up and Lenglet had his chances to establish himself but failed in last two seasons after being pretty ok in his first year. He shouldn't be unquestionable starter again and don't think he will (he's clearly a CB4 for Koeman right now) but think he should still get some game time against easier opponents to see if his form has improved. He could still be a useful squad player to have around as he's extremely durable and never gets injured (the same reason why I wanted to keep Griezmann knowing other forwards mostly can't stay fit).
I don't think Araujo and Eric will become our longterm CB pair (would be very happy to be wrong about that though as it would save us a lot of money and time trying to find at least one new starting quality CB) but in first transitional post-Messi season we should at least get a clearer opinion if and how they can work together. If we could somehow combine Araujo's physical profile with Garcia's on the ball skills (and his suposed leadership qualities which we haven't seen so far but it's still very early days for him) into one player we would get a close to ideal modern day Barca profile CB for mostly free. Sadly we can't do that so the next thing is we should find out if their strenghts can fit together into at least somewhat respectable unit (and given what we've seen at the position in recent years an improvement shouldn't really be that hard to achieve). I think they should be more than good enough for most La Liga teams. What would happen against top European teams is another question but anyone realistic enough knows this team has no business being competitive against likes of Bayern, City or PSG regardless of who our CBs are so why not at least try something new instead of keep playing the same players who have consistently proven in last years they're not up to the task (anymore)?
This point stands not only for a CB positon but for the rest of the team as well. Give the kids a chance. It can't get much worse but at least they can learn something and hopefully become better.