Nothing is doom and gloom here.
probably the concrete of a medium used. More perlite or similar would help. Avoid the soils with big chunks of wood chips or anything else that size.
overwatering - either running so much water through it it drowns the roots annd the plant droops or too freequently watering which raises risk of root rot. This really should never be a concern. The only reason it'd be a concern is if someone isn't adhering to well-established irrigation practices..
1) full saturate (absolutely not over-watering).
2) wait for appropriate dryback and repeat. In this soil showns, wait for 1" deep to dry before repeating... loss of weight is a better trigger.
Simple. If it's soilless, you simply add 10% runoff religiously each time and fertilize every time. If you are choosing a volume of water to provide off the top of your head, you are doing it wrong. You give the volume that gets the job done as outlinded by the simple 1-step process above - fully saturate. Partial watering leads to problems, too.
nutrients are nutrients, more times than not. Give the right ratio and concentration and the plant remains healthy, yes.
use size-appropriate pots for better growth rates. Big pot, tiny plant results in wonky watering practices. The plant may have been concentrating more on the rootzone than above ground growth.