Reception Only — Rude?

My fiancé and I get married in April 22nd.


Due to potential COVID restrictions, and based on our venue’s prior handling of county mandates, (plus my crippling social anxiety!) we have decided to do a private ceremony (literally us, our parents and the officiant) immediately followed by a family dinner.
The dinner is for 50 — family and a few very close friends — and we aren’t planning for a professional DJ, just a phone + bluetooth speaker. We chose a restaurant that we’ve loved since we started dating. They’re a restaurant/cafe that is known for farm-to-table, locally sourced menus and a really cool vibe.
We were pretty excited to put our plan together, especially given our budget limitations and COVID concerns. However, my fiancée’s mother has recently decided to inform him that our day is not going to be ‘nice enough’ or memorable. From what he told me, it sounds as if she believes everyone will be insulted since they weren’t invited to the ceremony.
Is it rude? My side has been super supportive, with everyone making it known that they understand and are just as excited (some even more so — they’re not big ceremony people) and seem to be looking forward to it. His family members that I’ve spoken with have said the same. I’m not sure if it’s just his mom projecting, or if everyone in his family has just been lying to me about their opinion, but I’m feeling a bit torn now.
We’re fully paying for this, no support from either side, apart from my mom covering the $200 for my dress and veil, and we’ve never wanted a big event. I originally wanted to elope, but my fiancée really wanted to share the excitement with his family, so this seemed like the perfect compromise.
Would you be insulted, if you were invited to a dinner-only event?
Any input is welcome — I’m sifting through a lot of personal problems this week, and am at the point where I’m getting somewhat emotional if I think about it for too long 😂