The last time either of the major USA political parties had an old style political convention was over 40 years ago. These days, conventions tend to be largely orchestrated showcases although there is an occasional fly in the ointment.
The fact that there are so many candidates for the 2020 Democratic nomination makes it more likely than usual. However, the movement away from the caucuses to the primaries has made it improbable. Voters in the later primaries tend to shy away from those candidates that have had poorer results in the earlier primaries.
There has also been the super delegate ingredient in the Democratic party.
The result is that these days one of the candidates already has 50% of the delegates before the convention begins.
This has made the party conventions relatively boring to anyone who is not either a political wonk or a raving fan of the presumed nominee.
This can be seen in the fact that most of the news organizations tend to give very little airtime to the speaker's platform.
Conventions of the past were not this way. I can remember my Dad in 1968 sitting down in front of a radio with a sheet of paper to keep a tally of the voting during the Democratic convention. My Dad was not only NOT a member of the Democratic party, he was also an old style independent. Meaning that he was relatively clueless at that time as to the major differences between the Republican and Democratic parties. He did not vote straight ticket and that year he ended up voting for Nixon. But there he was on the night in which the Democratic party was voting for a nominee planning to stay up late into the night to find out who they would nominate.
You wouldn't see that kind of interest among the general public these days!
For what it's worth, I am not planning on watching or listening to the political conventions of 2020 and have very little interest outside of a small degree of curiosity in who is picked to be the Democratic nominee.