You've been victimized by a buggy upgrade from a previous perpetually licensed version of LR. Your System Info shows you with LR Classic 7.4 and a Perpetual license. However, Adobe doesn't sell perpetual licenses for LR 7, just Creative Cloud subscriptions. At some point, you were presented with a misleading message from LR to "update" which then incorrectly installed LR 7. Besides presets not working, there are a number of other features that will misbehave for you.
See here for how you might proceed: Lightroom Classic: Presets not working/ perpetual license glitch | Photoshop Family Customer Community
Thank you John!
Do you think that another solution would be to wait for Adobe to release a 7.5 version that would fix the problem?
I will try to answer for John-
No. it will NOT fix.
You only have two options-
1. Return to using Perpetual Version 6.14
2. Start a paid subscription to Creative Cloud and make Classic v 7.4 a 'Legitimate Legal' install of Lightroom.
If you already are a Subscriber (pay monthly/annually) then you must contact Adobe Customer Care to correct the problem.