Most likely not a problem at all and probably have always been there from the beginning.
What makes the structural strength of the aquarium is all the silicone between the glass, this can have flaws without any issues because there is a lot of it to hold it together.
The triangular silicone seam in the corners on the inside of the glass is the most important sealant that should not show any significant damage. But also this can have minor delamination without causing problems as long as it isn't delaminated all the way then it still seals... There aren't many 100% perfect aquariums built, for that, you would need to buy it in the top range, brands such as ADA that advertise with Low Iron super clear glass and minimal silicone work that are perfect and also have that perfect price tag.
Not sure if that is enough for you. And I guess all this is easier for me to say than for you to feel insured... You probably like everybody don't want to read things like "Probably" and or "Most likely" That's understandable those words aren't reassuring but that's the way it is. You'll never have a 100% guarantee, maybe the first year from the builder after that you are on your own. That goes for all of us nobody excluded. And a lot of us oldtimers in the hobby have seen leaking aquariums at one time or another, these things can happen. Hence 30 years ago I had one exploding on me, ripping apart a glass panel in a split second, crack SPLASH! empty. That was my first bad aquarium stand experience and it still took 3 years to crack it. Only 1 in 50 years with all together over 10 aquariums in the hobby I guess that's a pretty acceptable risk 1 in over 10 in 50 years. But still, I've seen it happen in front of my eyes.
Sorry for breaking it so bluntly and honestly to you.
This is from the backside of one of the tanks I built myself... And it looks worse than it is...
View attachment 212335
It's still up and running since 2018 without any issues.
View attachment 212336