Lack of experience is a general term. I would first try to ask your contact persons a bit more about why you were not a good fit; which areas of your portfolio show the lack of experience. Don't demand an answer, just be polite and ask for their feedback so you can improve your work.
The biggest problem I see with your portfolio is that the final solution does not match the initial task.
1) The Internet of Collectibles. A bit confusing. You start with toys and collectibles, then you include IOT and then at the end they are just everyday products that look like random toys. These are neither toys, nor collectibles and probably won't function as well as the intended products. The modeling and rendering also looks a bit primitive. No part-lines or charging ports or cables....
2) Housewares - Sponge. Good exploration of different products. At the end you chose sponge sanitation. The problem is you only show 5 directions so there is no concept development, refinement, etc. Instead of showing a mood board supporting your CMF decisions you decided to copy another brand's CMF. The styling seems too harsh and niche, specially for a low income mass market appeal. How is it waterproof, where is the battery, how do you recharge it, etc.
3) Coffee Maker - Again, a bit confusing. Statement mentions new brand language, line of products, etc. Sketches are more of a re-design of a coffee maker/pot. I don't know what you achieve by hanging it? The main coffee maker still occupies space in the countertop. The CMF doesn't work. Cream & blue? It doesn't fit in a sophisticated kitchen, it sticks out on the jpeg with the traditional kitchen too. How tall is the coffee pot now? Does it even fit under kitchen cabinets? Do you know the standard height of cabinets? How do you heat the carafe, where is the heating element, water reservoir, coffee filter, etc. A coffee maker is a very simple product, you should at least attempt at addressing all of this.
4) Helmet - Again, you start with sustainability but present a higher visibility solution. It seems like you spent more time on the fin than the actual helmet.
5) Furniture - Interesting concept. Nice to see a full size prototype.
I think the biggest problem is not sticking to your initial premise or problem. Most of your projects seem like you started with a premise but then guided your work by your favorite idea. At the end you should ask yourself "If I saw this coffee maker at Target, BestBuy, etc., next to the other coffee makers (Braun, Mr. Coffee, Keurig, Cuisinart, etc.) would I buy mine?" How is mine better than the other ones?
Keep going and rework some of your projects. Keep trying to get a junior position but also paid or unpaid internships. You will learn a lot. If I were to hire you I would have to spend months training your thought process.