After using Roll20 and Fantasy Grounds from both sides of the table, I landed on Foundry VTT and never looked back.
It’s not free, but the value for the price is almost unheard of these days. Andrew and his team have a knack for finding a good balance between power, flexibility, ease of use, and beauty. Also, they engage with the community, and parts of the software are even open-source.
I would only suggest another VTT if the DM and players were all dirt poor, or if the DM had especially weak computer skills.
My only major complaint is that the official support channels and collective knowledge are locked behind Discord’s terms and conditions, which means I am denied access to both despite having a paid license. Fortunately, I don’t generally need support, and Foundry has plenty of unofficial channels as well.
Open-source enthusiasts might appreciate this:
https://github.com/owlbear-rodeo/owlbear-rodeo-legacy