I think it is not a question of preference but rather what is more sensible given the scenario at hand. If both companies are located in different continents, then you would very unlikely conduct an onsite DD. Moreover, I think the remote DD work very well, using the data room for exchanging the information – you can communicate with the targeted company very efficiently from my personal experience.
Both are important. Nowaday data rooms are digital and all documents are accessible digitally. Neverthless management interviews, site visits, customer interviews cannot always be done virtually. During COVID, remote DD’s were the only solution. We were ready to make an offer but we waited till we could visit in person the owners and the facilities. Better safe than sorry.
Both are important, but it depends on circumstances and the nature of the businesses. If it is an online business without any/much physical presence/footprint, it will mean that the online data rooms and DD would likely be more significant. Remote DD would also aid, especially for cross-country transactions and multinational companies.