Even as a relative casual, I only took a little over a month to cap all crafts at 60.

For one, it is entirely possible to cap a craft using a single type of crafted item.
E.g. Buy lots of cheap mats (logs for Carpenter, ore for BSM, ARM, GSM...etc), pop a 1k gil food to boost craftsmanship and auto-craft yourself to 60.

Lots of leves? You don't always have to craft the highest level item. Just do one, the one that costs the least.

My point? You don't need tons of inventory to level another craft.

SE does not need to cater to people who say "I don't want.". Its your problem/choice.

As for red scrips, it's hard/expensive to cap with 1 craft. The more crafts you have, the easier and cheaper it becomes.
- Heck, I can even wait a couple of days for my favorite recipe to turn up.
Some will view it as a penalty to single craft, some view it as a reward for capping multi-crafts. (Glass half-empty/half-full perception).
Again...Its your problem/choice.